Recent questions and answers in Class12

The inverse of $f(x)=x-[x],$ where $[x]$ is greatest integer function is

answered Sep 29, 2019 by pranav.awasarmol123

2 answers

If the variance of the random variable X is 9, the standard deviation of the random variable -4x+8 is?

answered Apr 6, 2019 by yachyuth2001

1 answer

What is $\displaystyle \int \frac {(x^2 +1)(x^2+2)}{(x^2+3)(x^2+4)} dx $ ?

answered Dec 13, 2018 by nikhilgautam7000

1 answer

Two fair dice are tossed once. The probability of getting an even number on the first die or a total of 8 is

answered Mar 18, 2018 by prakashtiwariaditya

2 answers

If $f_k(x) = \large\frac{1}{k}$$(\sin^k x + \cos^k x)$, where $x\in R$ and $k \geq 1$. The $f_4(x) - f_6(x)$ equals

answered Nov 15, 2017 by ityagi002

1 answer

Seven white balls and three black balls are randomly placed in a row. The probability that no two black balls are placed adjacently equals

answered Jul 9, 2017 by phaniajit2005

2 answers

Out of 7 consonents and 4 vowels, X number of words of 3 consonants and 2 vowels can be formed but Y number of groups of 3 consonents and 2 vowels can be formed. Find the value of X/Y .

answered Jun 21, 2015 by pady_1

1 answer

Find the velocity of the particle at the point(1,2,3)of a rigid body which is spinning about a fixed point (2,-1,3)with angular velocity 5 radians per second,the axis of rotation being in the direction of (-2i+j+2k)

asked May 26, 2015 by tintinsnowy81

0 answers

$\int \limits_0^{\pi} (x.sinx.sinx.cosx)dx$

answered Apr 9, 2015 by pady_1

1 answer

f(xy)=f(x)+f(y) . Then Prove that f(x) =Klog(x) where k is constant

answered Dec 17, 2014 by pady_1

1 answer

find area between the graphs log(x) , log(|x|) , |log(|x|)|

asked Dec 12, 2014 by vishavjeetmor

0 answers

If a square matrix A is such that $AA^T=I=A^TA$ then $|A|$ is equal to

answered Apr 25, 2014 by sreemathi.v

1 answer

If $A$ is square matrix of order $n\times n$ then adj(adj(A)) is equal to

answered Apr 25, 2014 by sreemathi.v

1 answer

The number of non trivial solutions of the system $x-y+z=0,x+2y-z=0,2x+y+3z=0$ is

answered Apr 25, 2014 by sreemathi.v

1 answer

If $A,B$ are two square matrices such that $AB=A$ and $BA=B$ then $A$ and $B$ are

answered Apr 25, 2014 by sreemathi.v

1 answer

If $A$ is orthogonal matrix then

answered Apr 25, 2014 by sreemathi.v

1 answer

The number of right inverse for the matrix $\begin{bmatrix}1&-1&2\\2&-1&1\end{bmatrix}$

answered Apr 25, 2014 by sreemathi.v

1 answer

If $ax^3+bx^2+cx+d=\begin{vmatrix}x^2&(x-1)^2&(x-2)\\(x-)^2&(x-2)^2&(x-3)^2\\(x-2)^2&(x-3)^2&(x-4)^2\end{vmatrix}$ then

answered Apr 25, 2014 by sreemathi.v

1 answer

The values of $\lambda$ and $\mu$ for which the equations $x+y+z=3,x+3y+2z=6,x+\lambda y+3z=\mu$ have

answered Apr 25, 2014 by sreemathi.v

1 answer

If $1+\sin x+\cos x\neq 0$ the value of $x$ for which $\begin{vmatrix}1&\sin x&\cos x\\\sin x&1&\cos x\\\cos x&\sin x&1\end{vmatrix}=0$ is

answered Apr 25, 2014 by sreemathi.v

1 answer

If $f(x)=\begin{vmatrix}\cos x&1&0\\1&2\cos x&1\\0&1&2\cos x\end{vmatrix}$ then $\int\limits_0^{\large\frac{\pi}{2}}2f(x)dx$ is equal to

answered Apr 25, 2014 by sreemathi.v

1 answer

If $A=\begin{vmatrix}a&b&c\\x&y&z\\p&q&r\end{vmatrix}$ and $B=\begin{vmatrix}q&-b&y\\-p&a&-x\\r&-c&z\end{vmatrix}$ then

answered Apr 24, 2014 by sreemathi.v

1 answer

If $A$ is an invertible matrix and B is a matrix then

answered Apr 24, 2014 by sreemathi.v

1 answer

If $A$ is a square matrix of order $n\times n$ then adj.(adj A) is equal to

answered Apr 24, 2014 by sreemathi.v

1 answer

$\begin{vmatrix}\log_3512&\log_43\\\log_38&\log_49\end{vmatrix}\times \begin{vmatrix}\log_23&\log_83\\\log_34&\log_34\end{vmatrix}=$

answered Apr 24, 2014 by sreemathi.v

1 answer

If $D_r=\begin{vmatrix}2^{r-1}&2.3^{r-1}&4.5^{r-1}\\\alpha&\beta&\gamma\\2^n-1&3^n-1&5^n-1\end{vmatrix}$ then the value of $\sum\limits_{r=1}^n D_r$ is

answered Apr 24, 2014 by sreemathi.v

1 answer

If the system of linear equations :$x+2ay+az=0,x+3by+bz=0,x+4cy+cz=0$ has a zero solutions then $a,b,c$

answered Apr 24, 2014 by sreemathi.v

1 answer

Value of the determinant $\begin{vmatrix} 10!&11!&12!\\11!&12!&13!\\12!&13!&14!\end{vmatrix}$ is

answered Apr 24, 2014 by sreemathi.v

1 answer

Let $C=\begin{bmatrix}C_{11}&C_{12}\\C_{21}&C_{22}\end{bmatrix}$ be a $2\times 2$ matrix and there exist $2\times 2$ matrices $A$ and $B$ such that $C=AB-BA$ then

answered Apr 24, 2014 by sreemathi.v

1 answer