Let $a,b,c\in \mathbb{R}$. If $f(x)=ax^{2}+bx+c$ is such that $a+b+c=3$ and
$f(x+y)=f(x)+f(y)+xy,\ \forall x,y\in \mathbb{R}$, then $\displaystyle \sum_{n=1}^{10} f(n)$ is equal to :
A man X has 7 friends, 4 of them are ladies and 3 are men. His wife Y also has 7 friends, 3 of them are ladies and 4 are men. Assume X and Y have no common friends. Then the total number of ways in which X and Y together can throw a party inviting 3 ladies and 3 men, so that 3 friends of each of X and Y are in this party, is:
If for a positive integer $n$, the quadratic equation
$x(x+1) + (x+1)(x+2) + \ldots + (x+n-1)(x+n) = 10n$
has two consecutive integral solutions, then $n$ is equal to :
Let $\omega$ be a complex number such that $2\omega + 1 = z$ where $z = \sqrt{-3}$.
If
$\begin{vmatrix}
1 & 1 & 1 \\
1 & -\omega^{2}-1 & \omega^{2} \\
1 & \omega^{2} & \omega^{7}
\end{vmatrix}
= 3k$,
then $k$ is equal to :
If two different numbers are taken from the set {0,1,2,3,...,10} then the probability that their sum as well as absolute difference are both multiple of 4, is :
For three events A, B and C, P(Exactly one of A or B occurs) = P(Exactly one of B or C occurs) = P(Exactly one of C or A occurs) = $\dfrac{1}{4}$ and P(All the three events occur simultaneously) =$ \dfrac{1}{16}$. Then the probability that at least one of the events occurs, is :
Let $\vec{a}=2\hat{i}+\hat{j}-2\hat{k}$ and $\vec{b}=\hat{i}+\hat{j}$.
Let $\vec{c}$ be a vector such that $|\vec{c}-\vec{a}|=3$, $|(\vec{a}\times\vec{b})\times\vec{c}|=3$ and the angle between $\vec{c}$ and $\vec{a}\times\vec{b}$ is $30^\circ$.
Then $\vec{a}\cdot\vec{c}$ is equal to :
Let k be an integer such that the triangle with vertices (k,-3k), (5,k) and (-k,2) has area 28 sq. units. Then the orthocentre of this triangle is at the point :
Let $I_n=\int \tan^{n}x,dx,\ (n>1)$.
If $I_4+I_6=a\tan^{5}x+bx^{5}+C$, where $C$ is a constant of integration,
then the ordered pair $(a,b)$ is equal to :
Twenty meters of wire is available for fencing off a flower-bed in the form of a circular sector. Then the maximum area (in sq. m) of the flower-bed, is :
If for $x\in\left(0,\dfrac14\right)$, the derivative of
$\tan^{-1}\left(\dfrac{6x\sqrt{x}}{1-9x^{3}}\right)$ is $\sqrt{x}\cdot g(x)$, then $g(x)$ equals :
Let p(x) be a quadratic polynomial such that p(0)=1. If p(x) leaves remainder 4 when divided by x-1 and it leaves remainder 6 when divided by x+1, then:
If all the words, with or without meaning, are written using the letters of the word QUEEN and are arranged as in English dictionary, then the position of the word QUEEN is :
Consider an ellipse, whose center is at the origin and its major axis is along the $x$-axis. If its eccentricity is $\dfrac{3}{5}$ and the distance between its foci is $6$, then the area (in sq. units) of the quadrilateral inscribed in the ellipse, with the vertices at the vertices of the ellipse, is :
Three persons P, Q and R independently try to hit a target. If the probabilities of their hitting the target are $\dfrac{3}{4},\ \dfrac{1}{2}$ and $\dfrac{5}{8}$ respectively, then the probability that the target is hit by $P$ or $Q$ but not by $R$ is :
The mean age of 25 teachers in a school is 40 years. A teacher retires at the age of 60 years and a new teacher is appointed in his place. If now the mean age of the teachers in this school is 39 years, then the age (in years) of the newly appointed teacher is :
If two parallel chords of a circle, having diameter 4 units, lie on the opposite sides of the center and subtend angles $\cos^{-1}\left(\dfrac{1}{7}\right)$ and $\sec^{-1}(7)$ at the center respectively, then the distance between these chords, is :
The number of ways in which $5$ boys and $3$ girls can be seated on a round table if a particular boy $B_1$ and a particular girl $G_1$ never sit adjacent to each other, is :
The coefficient of $x^{-5}$ in the binomial expansion of
$\left( \dfrac{x+1}{x^{\frac{2}{3}} - x^{\frac{1}{3}} + 1} ;-; \dfrac{x-1}{x - x^{\frac{1}{2}}} \right)^{10}$, where $x \neq 0,1$, is:
For two $3 \times 3$ matrices $A$ and $B$, let
$A + B = 2B^T$ and $3A + 2B = I_3$,
where $B^T$ is the transpose of $B$ and $I_3$ is $3 \times 3$ identity matrix. Then:
The function $f : \mathbb{N} \to \mathbb{N}$ defined by
$f(x) = x - 5\left\lfloor \dfrac{\pi x}{5} \right\rfloor$,
where $\mathbb{N}$ is the set of natural numbers and $\lfloor x \rfloor$ denotes the greatest integer $\le x$, is:
The two adjacent sides of a cyclic quadrilateral are $2$ and $5$ and the angle between them is $60^\circ$.
If the area of the quadrilateral is $4\sqrt{3}$, then the perimeter of the quadrilateral is:
The equation
$\operatorname{Im}\left( \dfrac{iz - 2}{z - i} \right) + 1 = 0,; z \in \mathbb{C},; z \neq i$
represents a part of a circle having radius equal to:
Let $E$ and $F$ be two independent events.
The probability that both $E$ and $F$ happen is $\dfrac{1}{12}$ and the probability that neither $E$ nor $F$ happens is $\dfrac{1}{2}$.
Then a value of $\dfrac{P(E)}{P(F)}$ is:
The sum of $100$ observations and the sum of their squares are $400$ and $2475$, respectively.
Later on, three observations, $3,4$ and $5$, were found to be incorrect.
If the incorrect observations are omitted, then the variance of the remaining observations is:
If the vector $\vec{b} = 3\vec{j} + 4\vec{k}$ is written as the sum of a vector $\vec{b_1}$ parallel to
$\vec{a} = \vec{i} + \vec{j}$ and a vector $\vec{b_2}$ perpendicular to $\vec{a}$,
then $\vec{b_1} \times \vec{b_2}$ is equal to:
From a group of $10$ men and $5$ women, four-member committees are to be formed, each of which must contain at least one woman.
Then the probability for these committees to have more women than men is:
If $2x = y^{\tfrac{1}{5}} + y^{-\tfrac{1}{5}}$ and
$(x^{2} - 1)\dfrac{d^{2}y}{dx^{2}} + \lambda x\dfrac{dy}{dx} + ky = 0$,
then $\lambda + k$ is equal to:
A square, of each side $2$, lies above the $x$-axis and has one vertex at the origin.
If one of the sides passing through the origin makes an angle $30^\circ$ with the positive direction of the $x$-axis,
then the sum of the $x$-coordinates of the vertices of the square is:
If
$\displaystyle f\left(\frac{3x-4}{3x+4}\right) = x + 2,; x \ne -\frac{4}{3}$
and
$\displaystyle \int f(x),dx = A\ln|1-x| + Bx + C,$
then the ordered pair $(A,B)$ is equal to
(where $C$ is a constant of integration):
Let $a,b\in\mathbb{R}$, $(a\neq 0)$. If the function $f$ defined as
$f(x)=
\begin{cases}
\dfrac{2x^{2}}{a}, & 0\le x<1 \\
a, & 1\le x<\sqrt{2} \\
\dfrac{2b^{2}-4b}{x^{3}}, & \sqrt{2}\le x<\infty
\end{cases}$
is continuous in the interval $[0,\infty)$, then an ordered pair $(a,b)$ is :