TU IOST | Mathematics
In the followings, the statement is
Answer: Rara lake is in Pokhara
2080 paper, Q1: explanation →If $S={x: x\in\mathbb{R} \text{ and } x^{2}+4=0}$ then the set $S$ is
Answer:
2080 paper, Q2: explanation →The set is a collection of
Answer: longest rivers of Nepal
2080 paper, Q3: explanation →$S={x: x\ge -2, x\in\mathbb{R}}$ is represented by
Answer: $[-2,\infty)$
2080 paper, Q4: explanation →$|x-5|\le 3$ has values of $x=$
Answer: $[2,8]$
2080 paper, Q5: explanation →The ordered pair $(a,b)$ for $(2a-1,-3)=(1,b+3)$ is
Answer: $(1,-6)$
2080 paper, Q6: explanation →If a function $f:\mathbb{R}\to\mathbb{R}$ be defined by $f(x)=2x+5$ then the pre-image of $7$ in $\mathbb{R}$ is
Answer:
2080 paper, Q7: explanation →The domain of the function $f:\mathbb{R}\to\mathbb{R}$ defined by $f(x)=\sqrt{1-x^{2}}$ is
Answer: $[-1,1]$
2080 paper, Q8: explanation →The base of an exponential function $y=a^{x}$ passing through $(2,4)$ is
Answer:
2080 paper, Q9: explanation →$3^{2\log_3 x}=$
Answer: $x^{2}$
2080 paper, Q10: explanation →The function $f(x)=x^{2}-2$ is
Answer: an even function
2080 paper, Q11: explanation →A number which can be expressed in the form $p/q$, $q\ne 0$; $p,q$ are integers, is called
Answer: a rational number
2080 paper, Q12: explanation →The sum of an infinite geometric sequence $a, ak, ak^{2},\dots$ exists if
Answer: $-1<k<1$
2080 paper, Q13: explanation →If $2k+1$, $3k+2$ and $5k+1$ are in A.P., then $k=$
Answer:
2080 paper, Q14: explanation →The matrix $\begin{pmatrix}0&1\-1&0\end{pmatrix}$ is
Answer: skew-symmetric
2080 paper, Q15: explanation →If $A=\begin{pmatrix}-5&3\2&-1\end{pmatrix}$ then $A^{-1}=$
Answer: $\begin{pmatrix}1&3\-2&-5\end{pmatrix}$
2080 paper, Q16: explanation →If $A=\begin{vmatrix}2a+1&1\3a&2\end{vmatrix}=0$, then $a=$
Answer:
2080 paper, Q17: explanation →A square matrix is said to be singular if
Answer: $|A|=0$
2080 paper, Q18: explanation →If the roots of the equation $px^{2}+qx+r=0$ are equal in magnitude but opposite in sign, then
Answer: $q=0$
2080 paper, Q19: explanation →If the discriminant of the equation $x^{2}+kx+4=0$ is zero then $k=$
Answer:
2080 paper, Q20: explanation →If $i$ is the imaginary unit, then $\dfrac{1-i}{1+i}=$
Answer:
2080 paper, Q21: explanation →The square roots of a complex number $5+12i$ is
Answer: $\pm(3+2i)$
2080 paper, Q22: explanation →Which is not a rational number?
Answer:
2079 paper, Q1: explanation →If $A$ and $B$ are non-empty sets and $A\subset B\subset U$, then $A\cap B=$
Answer:
2079 paper, Q2: explanation →If $|x-1|\le 5$ then $x=$
Answer: $[-4,6]$
2079 paper, Q3: explanation →If $\log_a x=y$ then $x=$
Answer: $a^{y}$
2079 paper, Q4: explanation →If $f:\mathbb{R}\to\mathbb{R}$ is defined by $f(x)=3x-2$, for $x\in\mathbb{R}$, then the pre-image of $10$ in $\mathbb{R}$ is
Answer:
2079 paper, Q5: explanation →The domain of the function $f(x)=\sqrt{16-x^2}$ is
Answer: $[-4,4]$
2079 paper, Q6: explanation →A sentence $x+5=4$ is
Answer: not a statement
2079 paper, Q7: explanation →If $p$, $q$ and $r$ are in G.P., then
Answer: $q^2=pr$
2079 paper, Q9: explanation →If $k+3$, $4k+7$ and $3k-1$ are in AP then the sequence is
Answer: $7,9,11$
2079 paper, Q10: explanation →The solution set of $3x+5>2x+1$ is
Answer: $x>-4$
2079 paper, Q36: explanation →If A and B are non-intersecting and disjoint sets then $n(A\cup B)$ is equal to
Answer: $n(A)+n(B)$
PU 2079 paper, Q26: explanation →If $2\le y\le 3$, then
Answer: $(y-2)(y-3)\le 0$
PU 2079 paper, Q27: explanation →The domain of the function $f(x)=\log(1-x)+\sqrt{x^2-1}$ is
Answer: $(-\infty,-1)$
PU 2079 paper, Q28: explanation →If $f(x)=x^3+\tan x$, then $f(x)$ is
Answer: Odd function
PU 2079 paper, Q29: explanation →$i+i^2+i^3+i^4=$
Answer: 0
PU 2079 paper, Q30: explanation →The quadratic equation whose roots are $\frac12$ and $-\frac12$ is
Answer: $4x^2-1=0$
PU 2079 paper, Q31: explanation →The sum of the series $5+\frac52+\frac54+\cdots$ to infinity is
Answer: 10
PU 2079 paper, Q32: explanation →The angles of a triangle are in A.P. and the least angle is $30^\circ$. The greatest angle in radian is
Answer: $\frac{\pi}{2}$
PU 2079 paper, Q33: explanation →If A is a square matrix, then $(A+A^{T})$ is a
Answer: Symmetric matrix
PU 2079 paper, Q40: explanation →If the ratio of cost price and selling price of an article is 2:3 then
Answer: $\text{Profit},% = 50%$
2078 paper, Q41: explanation →If $a+b+c=0$ in quadratic equation $ax^2+bx+c=0$ then roots of quadratic equation is
Answer: $1$ and $\frac{c}{a}$
2078 paper, Q46: explanation →If $(m+n)^{th}$ term of a G.P is $p$ and $(m-n)^{th}$ term is $q$ then $m^{th}$ term is
Answer: $\sqrt{pq}$
2078 paper, Q47: explanation →$(a+b-c)x^2+(c+a-b)x+(b+c-a)=0$ and $a+b+c=0$ then roots of quadratic equation, if a, b, and c are rational
Answer: rational
2078 paper, Q48: explanation →The quadratic equation whose roots are $\frac{3}{5}$ times the roots of quadratic equation $x^2-8x+7=0$
Answer: $25x^2-120x+63=0$
2078 paper, Q49: explanation →$S_n=\frac{a(1-r^n)}{1-r}$, sum of geometric progression is true if
Answer: $|r|<1$
2078 paper, Q50: explanation →Square roots of $(3+4i)$ are
Answer: $\pm(2+i)$
2078 paper, Q51: explanation →$|x-a|=$
Answer: $(a-x)$ if $x<a$
2078 paper, Q59: explanation →Which of the following statements is are true
Answer: if $a_{ij}=-a_{ji}$ $\forall$ $i$ and $j$ and $a_{ij}=0$ for $i=j$ then matrix is called skew-symmetric matrix
2078 paper, Q62: explanation →Find the inverse of the function $f(x)=3x^4+2$
Answer: $\sqrt[4]{\frac{x-2}{3}}$
2078 paper, Q63: explanation →Domain of the function $f(x)=\frac{x^2-4}{x-2}$ is
Answer: $R-{2}$
2078 paper, Q64: explanation →$\log_2\sqrt{2\sqrt{2\sqrt{2\sqrt{2\sqrt{2\sqrt{2}}}}}}$
Answer: $\frac{63}{64}$
2078 paper, Q65: explanation →$\begin{vmatrix}1&2&3\4&5&6\7&8&9\end{vmatrix}=$
Answer:
2078 paper, Q66: explanation →If $A={x:x\in R,\sqrt{2x^2-1}=-1}$ then A is
Answer: null set
2078 paper, Q69: explanation →Non-intersecting lines are
Answer: Inconsistent and independent
2078 paper, Q72: explanation →If the price of petrol in Nepal is increased by 25%. How much percent must a Saral Shikshya student reduce his consumption of petrol so as not to increase his expenditure on petrol?
Answer: 20%
2078 paper, Q73: explanation →If A earns $33\frac13%$ more than B, how much percent does B earn less than A?
Answer: 25%
2078 paper, Q74: explanation →If $a^2+b^2+c^2-ab-bc-ca=0$ then $a:b:c$ is
Answer: 1:1:1
2078 paper, Q75: explanation →The speed of a boat when traveling downstream is 32km/hr, whereas when travelling upstream it is 28 km/hr, what is the speed of a boat in still water?
Answer: 30km/hr
2078 paper, Q77: explanation →The surface area of a cube is $150\text{cm}^2$. Its volume is
Answer: $125\text{cm}^3$
2078 paper, Q78: explanation →If the supply function $P_s=160+2Q^2$ and the demand function is $P_d=240-3Q^2$. The market equilibrium price is
Answer: 192
2078 paper, Q79: explanation →If $n(\cup)=200, n(A)=80, n(B)=60$, what is the maximum value of $n(A\cup B)$?
Answer:
2077 paper, Q41: explanation →$-1\le x\le 11$ is equivalent to
Answer: $|x-5|\le 6$
2077 paper, Q42: explanation →Range of $y=x^2-4x+5$ is
Answer: $[1,\infty)$
2077 paper, Q43: explanation →If $\log_9 81=x$, then $x$ is
Answer:
2077 paper, Q45: explanation →If $x=\log_a bc,\ y=\log_b ca,\ z=\log_c ab$, then $\frac{1}{x+1}+\frac{1}{y+1}+\frac{1}{z+1}=$
Answer:
2077 paper, Q46: explanation →$1.5+0.015+0.00015+\dots=$
Answer: $\frac{50}{33}$
2077 paper, Q47: explanation →Value of $2^{1/4}\cdot 4^{1/8}\cdot 8^{1/16}\cdot 16^{1/32}\cdots\infty$ is
Answer:
2077 paper, Q48: explanation →The system $kx-2y=0,\ x+3y=0$ has a unique solution if
Answer: $k\ne -\frac23$
2077 paper, Q50: explanation →If one root of $ax^2+bx+c=0$ is the square of the other, then
Answer: $b^3+a^2c+ac^2=3abc$
2077 paper, Q51: explanation →The amplitude of $1-i$ is
Answer: $315^\circ$
2077 paper, Q52: explanation →The mean proportional between $4$ and $16$ is
Answer:
2077 paper, Q53: explanation →A is 25% more efficient than B in working. If A takes 15 days less than B to complete a work, in how many days will they finish it working together?
Answer: $25\frac57$ days
2077 paper, Q54: explanation →A plane left 30 minutes later than scheduled and, to reach its destination 1500 km away in time, it had to increase its speed by 250 km/hr. Its usual speed is
Answer: km/hr
2077 paper, Q55: explanation →The present worth of Rs 2040 due 4 years hence at 5% p.a. is
Answer: Rs.
2077 paper, Q56: explanation →The interest rate at which a sum doubles in 10 years is
Answer:
2077 paper, Q57: explanation →Profits in the partnership of Bikram, Bishal and Binita are shared in ratio $1:2:3$. If Bikram's share is Rs. 300, what is Binita's share?
Answer: Rs. 900
2077 paper, Q58: explanation →HCF of $n!,\ (n+1)!$ and $(n+2)!$ is
Answer:
2077 paper, Q61: explanation →Every rational number is also
Answer: a real number
2076 paper, Q41: explanation →If $a-ib=\frac{3-2i}{3+2i}$ then $a^{2}+b^{2}=$
Answer:
2076 paper, Q42: explanation →Given $U={1,2,3,\ldots,15}$, $A={x: x\ge 8}$, $B={x: x\le 4}$ then $\overline{A\cap B}=$
Answer:
2076 paper, Q43: explanation →Which are the equal ordered pairs?
Answer: (4,2),(4,2)
2076 paper, Q44: explanation →$S_{\infty}=\frac{a}{1-r}$, where $a, r$ and $S_{\infty}$ denote first term, common ratio and sum to infinity. If
Answer: $|r|<1$
2076 paper, Q45: explanation →If ${}^{21}C_{x}={}^{21}C_{y}$ then which is true?
Answer: either (b) or (c)
2076 paper, Q46: explanation →Which is not correct?
Answer: $(AB)^{T}=A^{T}B^{T}$
2076 paper, Q47: explanation →Which is not correct? (a) $\begin{vmatrix}a_1&a_2&a_3\b_1&b_2&b_3\c_1&c_2&c_3\end{vmatrix}=\begin{vmatrix}a_1&b_1&c_1\a_2&b_2&c_2\a_3&b_3&c_3\end{vmatrix}$; (b) $\begin{vmatrix}0&a_2&a_3\b_1&0&b_3\c_1&c_2&0\end{vmatrix}=0$; (c) a determinant with a row of zeros is $0$; (d) adding $k$ times one column to another leaves the determinant unchanged.
Answer: (b)
2076 paper, Q48: explanation →Which is correct?
Answer: all of them
2076 paper, Q51: explanation →The domain of $y=f(x)=\frac{1}{x}$ is
Answer: $R-{0}$
2076 paper, Q52: explanation →Let $f:R\to R$ be defined by $f(x)=10x-7$ then $f^{-1}(x)=$
Answer: $\frac{x+7}{10}$
2076 paper, Q53: explanation →If $t$ be a positive real number then the least value of $t+\frac{1}{t}$ is:
Answer:
2076 paper, Q54: explanation →The system of linear equations $2x+3y=5$ and $4x+6y=9$ are
Answer: Inconsistent & dependent
2076 paper, Q71: explanation →The degree of polynomial equation $ax^{2}+bx+c=0$ is
Answer: 2
2076 paper, Q72: explanation →If one root of a quadratic equation in the real coefficient is $\sqrt{2}$ then equation is
Answer: $x^{2}-2=0$
2076 paper, Q73: explanation →If four quantities $a,b,c$ and $d$ are such that $a:b=3:4$, $b:c=6:7$ and $c:d=8:9$, then the ratio between $a$ and $d$ is
Answer: $4:7$
2076 paper, Q75: explanation →By selling 175 pens, a stationary store gains the selling price of 50 pens. What is his gain percent?
Answer:
2076 paper, Q76: explanation →A, B, C and D enter into a partnership. A, B, C subscribe $\frac{1}{3},\frac{1}{4},\frac{1}{5}$ of the capital respectively and D, the rest. What is the share of profit of D if the total profit is Rs. 24600?
Answer: Rs. 5330
2076 paper, Q77: explanation →If USD 1 = Rs. 78.15, how many US dollars are equivalent to Rs. 10,000?
Answer: USD 127.96
2076 paper, Q78: explanation →The effective rate corresponding to 10% p.a. convertible quarterly is
Answer: 10.4%
2076 paper, Q79: explanation →The present value of an immediate annuity is; where symbols have their usual meaning
Answer: $\frac{p}{i}\left{1-\frac{1}{(1+i)^{n}}\right}$
2076 paper, Q80: explanation →If $\lim_{x\to a}\frac{x^{4}-a^{4}}{x-a}=256$, then $a=$
Answer:
2080 paper, Q35: explanation →$\lim_{x\to 0}\frac{\tan 3x}{x}=$
Answer:
2080 paper, Q36: explanation →A function $f(x)=2x+1$ is continuous at $x=1$, if
Answer: $\lim_{x\to0}f(x)=f(1)$
2080 paper, Q37: explanation →If $y=e^{\sin x^{2}}$, then $\frac{dy}{dx}=$
Answer: $2xy\cos x^{2}$
2080 paper, Q38: explanation →If $y=x^{3}-x^{2}$, then for $\frac{dy}{dx}=0$, $x=$
Answer: $0,2/3$
2080 paper, Q39: explanation →The function $f(x)=2x+5$ on $R$ is
Answer: increasing
2080 paper, Q40: explanation →$\int\frac{dx}{ax+b}=$
Answer: $\frac1a\log|ax+b|+c$
2080 paper, Q41: explanation →$\int\frac{dx}{2\cos^{2}x\sin^{2}x}=$
Answer: $-\cot2x+c$
2080 paper, Q42: explanation →$\int_1^3\frac{\sin(\ln t)}{t}dt=$
Answer: $1-\cos(\ln3)$
2080 paper, Q43: explanation →The area under the curve $y=x^{2}$ bounded by the x axis and the ordinates $x=1$ and $x=4$ is
Answer:
2080 paper, Q44: explanation →If $\lim_{x\to3}\frac{x^n-3^n}{x-3}=27$, then $n=$
Answer:
2079 paper, Q22: explanation →$\lim_{x\to0}\frac{\sin3x}{x}=$
Answer:
2079 paper, Q23: explanation →The function $f(x)=\begin{cases}\frac{x^2-x}{x-1}&x\ne1\k&x=1\end{cases}$ is continuous at $x=1$ for $k=$
Answer:
2079 paper, Q24: explanation →The differential coefficient of $\sin\theta$ with respect to $\cos\theta$ is
Answer: $-\cot\theta$
PU 2079 paper, Q39: explanation →$\lim_{n\to\infty}\frac{\sum n^2}{n^3} =$
Answer: $\frac{1}{3}$
2078 paper, Q42: explanation →$\lim_{x\to 1}(x-1)\tan\frac{\pi x}{2} =$
Answer: $-\frac{2}{\pi}$
2078 paper, Q43: explanation →If $y=\sqrt{\frac{1+\cos 2x}{1-\cos 2x}}$ then $\frac{dy}{dx}$ at $x=\frac{\pi}{2}$ is
Answer:
2078 paper, Q44: explanation →Derivative of $e^{\sqrt{x^2+a^2}}$ w.r.t $\sqrt{x^2+a^2}$
Answer: $e^{\sqrt{x^2+a^2}}$
2078 paper, Q45: explanation →The point of inflection of quadratic function is
Answer: does not exist
2078 paper, Q53: explanation →$\int_{-1}^{1}\sin^7x,dx=$
Answer:
2078 paper, Q58: explanation →$\int\frac{x}{x+1}dx=$
Answer: $x-\log(1+x)+c$
2078 paper, Q61: explanation →$\lim_{x\to64}\frac{\sqrt[6]{x}-2}{\sqrt[3]{x}-4}$
Answer: $\frac14$
2077 paper, Q70: explanation →$\lim_{x\to0}\frac{e^{\sin x}-1}{x}$
Answer:
2077 paper, Q71: explanation →$\frac{d}{dx}\cos^{-1}(\sin x)$
Answer:
2077 paper, Q73: explanation →If $x^py^q=(x+y)^{p+q}$ then $\frac{dy}{dx}=$
Answer: $\frac yx$
2077 paper, Q74: explanation →Derivative of $\sin^{-1}x$ is
Answer: $\frac1{\sqrt{1-x^2}}$
2077 paper, Q75: explanation →At a critical point, $f(x)$ is
Answer: stationary
2077 paper, Q76: explanation →The value of $\lim_{x\to\infty}\frac{\sqrt{x+1}}{\sqrt{x}+1}$ is
Answer:
2076 paper, Q55: explanation →The point of discontinuity of the function $f(x)=\frac{x^{3}-27}{x-3}$ is
Answer:
2076 paper, Q56: explanation →If $x+y=xy$ then $\frac{dx}{dy}=$
Answer: $\frac{1-x}{y-1}$
2076 paper, Q57: explanation →If $x=2at$, $y=at^{2}$ then $\frac{dy}{dx}=$
Answer:
2076 paper, Q58: explanation →If the total cost function $C=50x+5000$. The marginal cost function MC is
Answer:
2076 paper, Q59: explanation →The function $f(x)=2-3x$ is
Answer: Decreasing
2076 paper, Q61: explanation →$\int \log x,dx=$
Answer: $x\log x-x+c$
2076 paper, Q62: explanation →$\int_{-2}^{2}|x|,dx$ is equal to
Answer:
2076 paper, Q63: explanation →If the marginal cost of a product is given by $MC=8+6x-3x^{2}$ and the fixed cost is Rs. 150. The cost function is
Answer: $8x+3x^{2}-x^{3}+150$
2076 paper, Q64: explanation →The slope of the line $px+qy+c=0$ is
Answer: $-p/q$
2080 paper, Q25: explanation →If the length of the perpendicular from the point $(k,2)$ to $3x-4y+6=0$ is $2$, then $k=$
Answer:
2080 paper, Q26: explanation →The homogeneous equation is
Answer: $ax^{2}+xy+by^{2}=0$
2080 paper, Q27: explanation →The two lines represented by $kx^{2}+xy-y^{2}=0$ are perpendicular to each other if $k=$
Answer:
2080 paper, Q28: explanation →The distance of the point $(1,2,3)$ from origin is
Answer: $\sqrt{14}$
2080 paper, Q29: explanation →The direction ratios of the line $AB$ joining the points $A(4,5,0)$ and $B(2,3,4)$ are
Answer: $2,2,-4$
2080 paper, Q30: explanation →Equation of a line perpendicular to the line $x-3y+7=0$ is
Answer: $3x+y+10=0$
2079 paper, Q18: explanation →Equation of tangent at $(0,1)$ to the circle $x^2+y^2=1$ is
Answer: $y=1$
2079 paper, Q20: explanation →In a manufacturing company the production cost of $50$ items is Rs $5000$ in one day and Rs $12000$ to produce $150$ items in one day. If $x$ represents the number of items and $y$ represents the cost, the model equation is
Answer: $y=70x+1500$
2079 paper, Q38: explanation →A company finds the variable cost of Rs $.5$ per unit output and fixed cost of Rs $25$, where $Q$ is the number of outputs, then the total cost function, $T$ is
Answer: $T=5Q+25$
2079 paper, Q39: explanation →The circumcenter of an acute angled triangle lies
Answer: inside the triangle
PU 2079 paper, Q34: explanation →The area of the triangle whose vertices are $(1,2)$, $(2,3)$ and $(3,4)$ is
Answer: 0
PU 2079 paper, Q36: explanation →The equation of the line making an angle of $135^\circ$ with the positive x-axis and cutting an intercept 3 from the negative y-axis is
Answer: $x+y+3=0$
PU 2079 paper, Q37: explanation →The area of triangle with vertices $(1,2),(2,3)$ and $(3,4)$ is
Answer: 0 sq. unit
2078 paper, Q54: explanation →The polar coordinate of point $(-1,-\sqrt{3})$ is
Answer: $(2,\frac{4\pi}{3})$
2078 paper, Q56: explanation →The distance between parallel lines $3x+2y=6$ and $3x+2y=12$ is
Answer: $\frac{6}{\sqrt{13}}$
2077 paper, Q66: explanation →Angle between the lines represented by $2x^2-7xy+6y^2=0$ is
Answer: $\tan^{-1}(\pm\frac18)$
2077 paper, Q67: explanation →Length of the y-intercept made by the circle $x^2+y^2-8x+y-20=0$ is
Answer:
2077 paper, Q68: explanation →Radius of the circle $x^2+y^2+2x+3y+k=0$ is $\frac12$, then $k=$
Answer:
2077 paper, Q69: explanation →The equation $x=0$ represents
Answer: y-axis
2076 paper, Q49: explanation →The angle between the lines $xy=0$ is
Answer: $90^{0}$
2076 paper, Q50: explanation →The area of the circle $x^{2}+y^{2}=16$ is
Answer:
2076 paper, Q65: explanation →The equation $x^{2}+y^{2}=0$ represent
Answer: degenerate circle
2076 paper, Q74: explanation →$\sin(\cos^{-1}x)=$
Answer: $\sqrt{1-x^{2}}$
2080 paper, Q23: explanation →The general solution of $4\sin^{2}x=1$, for $n\in Z$ is
Answer: $x=n\pi\pm\frac{\pi}{6}$
2080 paper, Q24: explanation →The function $f(x)=\cos x$ is
Answer: an even function
2079 paper, Q8: explanation →In a triangle $ABC$, if $a=2\sqrt3$, $b=2$, $c=4$ then $A=$
Answer: $60^\circ$
2079 paper, Q15: explanation →The perimeter $2s$ of the triangle $ABC$ is
Answer: $a+b+c$
2079 paper, Q16: explanation →Area of the triangle $ABC$ is
Answer: $abc/4R$
2079 paper, Q17: explanation →$\sin(270^\circ-\theta)=$
Answer: $-\cos\theta$
PU 2079 paper, Q35: explanation →$\tan 15^\circ=$
Answer: $2-\sqrt3$
2078 paper, Q67: explanation →$\sin^{-1}\frac{1-x^2}{1+x^2}+\cos^{-1}\frac{2x}{1+x^2}$
Answer: none of these
2078 paper, Q70: explanation →$\cos x=$
Answer: All of these
2078 paper, Q71: explanation →Period of the function $\cos 2x$ is
Answer:
2077 paper, Q44: explanation →If $\tan^{-1}x+\tan^{-1}y+\tan^{-1}z=\frac{\pi}{2}$ then $xy+yz+zx=$
Answer:
2077 paper, Q62: explanation →Solution for $\sin\theta+\cos\theta=\sqrt2$ is
Answer: $2n\pi+\frac\pi4$
2077 paper, Q63: explanation →In any $\triangle ABC$, $2\cos A\sin C=\sin B$, then the triangle is
Answer: Isosceles
2077 paper, Q64: explanation →The maximum value of $\sin\theta\cos\theta$ is
Answer: $\frac{1}{2}$
2076 paper, Q60: explanation →The equation $\sin x+\cos x=2$ has
Answer: no solution
2076 paper, Q69: explanation →$\sin^{-1}x+\cos^{-1}x=$
Answer: $\frac{\pi}{2}$
2076 paper, Q70: explanation →If $y=e^{ax^2+b}$ then $\frac{dy}{dx}=$
Answer: $2axy$
2079 paper, Q25: explanation →If $x^2+y^2=25$ then $\frac{dy}{dx}$ at $(0,5)$ is
Answer:
2079 paper, Q26: explanation →The stationary point of the function $f(x)=x^2-6x+3$ is $x=$
Answer:
2079 paper, Q27: explanation →$\int e^{\log_e x},dx=$
Answer: $\frac{x^2}{2}+c$
2079 paper, Q28: explanation →$\int_0^1\frac{2x}{x^2+2},dx=$
Answer: $\log_e\frac32$
2079 paper, Q29: explanation →$\int\frac{1}{\cos^2x},dx=$
Answer: $\tan x+c$
2079 paper, Q30: explanation →Area bounded by the x-axis and the curve $y=x+2$ and the lines $x=0$ and $x=2$ is
Answer: sq. units
2079 paper, Q31: explanation →If $f(x)=2x+1$ then the approximate value of $f'(2)$ with $h=0.1$ is
Answer:
2079 paper, Q37: explanation →$\int\cot x,dx=$
Answer: $\ln(\sin x)+c$
2077 paper, Q77: explanation →$\int\frac{e^x-1}{e^x+1}dx=$
Answer: $2\log\left(e^{x/2}+e^{-x/2}\right)$
2077 paper, Q78: explanation →$\int\log x,dx=$
Answer: $x\log x-x$
2077 paper, Q79: explanation →Area of the region bounded by the curves $y^2=4ax$ and $x^2=4by$ is
Answer: $\frac{16ab}{3}$
2077 paper, Q80: explanation →The standard deviation of $3,6,9,12,15$ is
Answer: $3\sqrt{2}$
2080 paper, Q33: explanation →The probability of getting an ace of club or a king of spade from a pack of 52 cards is
Answer:
2080 paper, Q34: explanation →The probability of selecting a vowel from the English alphabet is
Answer:
2079 paper, Q34: explanation →The standard deviation of the data: $5, 10, 15, 20$ and $25$ is
Answer: $5\sqrt2$
2079 paper, Q35: explanation →Probability of an event E(x) is
Answer: $0\le p(\varepsilon)\le1$
2078 paper, Q80: explanation →If A and B are two independent events with $p(A)=\frac23$ and $p(B)=\frac35$ then $p(A\cup B)=$
Answer: $\frac{13}{15}$
2077 paper, Q59: explanation →For negative skewness
Answer: Mean<median<Mode
2077 paper, Q60: explanation →Which is the measure of dispersion?
Answer: range
2076 paper, Q67: explanation →Two brothers Mr. X and Mr. Y appear in an interview for a scholarship. The probability of Mr. X getting it is $\frac{1}{7}$ and of Mr. Y is $\frac{1}{5}$. What is the probability that both of them will get scholarship?
Answer: $\frac{1}{35}$
2076 paper, Q68: explanation →The direction of the vector $a\mathbf{i}+b\mathbf{j}$ is
Answer: $\tan^{-1}\left(\frac{b}{a}\right)$
2080 paper, Q31: explanation →The unit vector along $x\mathbf{i}-y\mathbf{j}$ is
Answer: $\frac{x\mathbf{i}-y\mathbf{j}}{\sqrt{x^{2}+y^{2}}}$
2080 paper, Q32: explanation →The unit vector of $i+j$ is
Answer: $\frac{i}{\sqrt2}+\frac{i}{\sqrt2}$
2079 paper, Q32: explanation →The direction of vector $v=ai+bj$ is
Answer: $\tan^{-1}\frac ba$
2079 paper, Q33: explanation →$\vec a\times\vec b=|\vec a||\vec b|\sin\theta,\hat\eta$, for any non-zero vectors $\vec a$ and $\vec b$
Answer: $\hat\eta$ is the unit vector along $\vec a\times\vec b$
2078 paper, Q68: explanation →If three equal forces $P$, $Q$ and $R$ are acting at a point of rigid body are in equilibrium, then the angle between any two forces is
Answer: $120^\circ$
2080 paper, Q47: explanation →A force equal to $4N$ acting vertically upwards is resolved into forces, one being horizontal and equal to $3N$. The magnitude of the other remaining force is
Answer:
2080 paper, Q48: explanation →If the acceleration of a particle, starting from rest is $5,m/sec^{2}$, then the velocity at the end of 3 seconds is
Answer: $15,m/sec^{2}$
2080 paper, Q49: explanation →A stone is thrown vertically upwards with a velocity of $30$ m/sec from the top of a tower and hits the ground after $10$ secs, then the height of the tower is
Answer: $200,m$
2080 paper, Q50: explanation →If $\begin{pmatrix}0&6\5+k&0\end{pmatrix}$ is a skew symmetric matrix then $k=$
Answer:
2079 paper, Q11: explanation →The value of $x$ for the determinant $\begin{vmatrix}x+3&0\1&1\end{vmatrix}=0$ is
Answer:
2079 paper, Q12: explanation →The value of $\sqrt{-8}\sqrt{-2}$ is
Answer:
2079 paper, Q13: explanation →The modulus of $\frac{1+i}{1-i}$ is
Answer:
2079 paper, Q14: explanation →The general formula for Newton-Raphson method is
Answer: $x_{n+1}=x_n-\frac{f(x_n)}{f'(x_n)}$
2080 paper, Q45: explanation →The approximate value of $\int_0^2x^{2}dx$ using midpoint rule with one interval is
Answer:
2080 paper, Q46: explanation →The following table gives two kinds of food and two kinds of vitamin: V1 needs 4 units of F1 and 8 of F2 with daily requirement 80; V2 needs 6 of F1 and 4 of F2 with requirement 100; cost per unit is Rs. 3 for F1 and Rs. 5 for F2. If qty of F1 $=x$, qty of F2 $=y$ then formulate the following problem to minimizing the cost.
Answer: min(z) = 3x+5y subject to 4x+8y >= 80, 6x+4y >= 100
2076 paper, Q66: explanation →The two lines represented by $ax^2+xy+by^2=0$ are perpendicular to each other if
Answer: $a+b=0$
2079 paper, Q19: explanation →The focus of the parabola $y^2=4x$ is
Answer: $(1,0)$
2079 paper, Q21: explanation →The pole of the line $y=mx+c$ with respect to the parabola $y^2=4ax$ is
Answer: $\left(\frac{c}{m},\frac{2a}{m}\right)$
PU 2079 paper, Q38: explanation →If a ball is projected vertically upwards with a velocity of $24.9$ m/s, then the maximum height described by the ball is
Answer: m
2079 paper, Q40: explanation →