MCQ
If $\frac{{d[f(x)]}}{{dx}} = g(x)$ for $a \le x \le b,$ then $\int_a^b {f(x)\,\,g(x)\,dx} $ equals
  • A
    $f(b) - f(a)$
  • B
    $g(b) - g(a)$
  • $\frac{{{{[f(b)]}^2} - {{[f(a)]}^2}}}{2}$
  • D
    $\frac{{{{[g(b)]}^2} - {{[g(a)]}^2}}}{2}$

Answer

Correct option: C.
$\frac{{{{[f(b)]}^2} - {{[f(a)]}^2}}}{2}$
c
(c) Let $I = \int_a^b {f(x)g(x)dx} $
Put $f(x) = t$ or $f'(x)dx = dt$ or $g(x)dx = dt$
==> $I = \int_{f(a)}^{f(b)} {tdt = \left| {\frac{{{t^2}}}{2}} \right|_{f(a)}^{f(b)}} = \frac{{{{[f(b)]}^2} - {{[f(a)]}^2}}}{2}$.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

For any $2 \times 2$ matrix $ A$, if $A(adj.\,\,A)$= $\left[ {\begin{array}{*{20}{c}}{10}&0\\0&{10}\end{array}} \right]$, then $|A|\, = $
Let $E ^{ C }$ denote the complement of an event $E$. Let $E _{1}, E _{2}$ and $E _{3}$ be any pairwise independent events with $P \left( E _{1}\right) > 0$ and $P \left( E _{1} \cap E _{2} \cap E _{3}\right)=0$ Then $P \left( E _{2}^{ C } \cap E _{3}^{ C } / E _{1}\right)$ is equal to
Let $a_n$ denote the number of all n-digit positive integers formed by the digits $0,1$ or both such that no consecutive digits in them are $0$ . Let $b_n=$ the number of such $n$-digit integers ending with digit $1$ and $c_n=$ the number of such $n$-digit integers ending with digit $0$ .

$1.$ Which of the following is correct?

$(A)$ $a_{17}=a_{16}+a_{15}$ $(B)$ $c_{17} \neq c_{16}+c_{15}$

$(C)$ $b_{17} \neq b_{16}+c_{16}$ $(D)$ $a_{17}=c_{17}+b_{16}$

$2.$ The value of $b_6$ is

$(A)$ $7$ $(B)$ $8$ $(C)$ $9$ $(D)$ $11$

Give the answer question $1$ and $2.$

Let $a, b, c, d, e$ be real numbers such that $a + b < c + d$, $b + c < d + e, c + d < e + a, d + e < a + b$. Then,
A jar contains $7$ white marbles and $3$ blue marbles. Given that the $4$ marbles are chosen from the jar at the same time, then the standard deviation of the number of the blue marbles choosen is $\frac {\sqrt a}{b}$  where $a$ and $b$ are co-prime numbers and $a$ is square free then $a + b$ is
If $z=x+iy$ and $\omega = \frac{{1 - iz}}{{z - i}}$ than $|\omega | = 1$ shows that in complex plane
Let $z _1$ and $z _2$ be two complex number such that $z _1$ $+z_2=5$ and $z_1^3+z_2^3=20+15 i$. Then $\left|z_1^4+z_2^4\right|$ equals$-$
The vertex of parabola is at $(1,2)$ and its axis is parallel to $y-$axis. If parabola passess through $(0,6)$, then its latus rectum is
If z is a complex number such that $|z| \geq 1$, then the minimum value of $\left| z +\frac{1}{2}(3+4 i)\right|$ is:
Consider the quadratic equation $\left( {c - 5} \right)\,{x^2} - 2cs + \left( {c - 4} \right) = 0$, $c \ne 5$. Let $S$ be the set of all integral values of $c$ for which one root of the equation lies in the interval $(0, 2)$ and its other root lies in the interval $(2, 3)$. Then the number of elements in $S$ is