Question
Let $f:R \to R$ be a differentiable function having $f(2) = 6,f'(2) = \left( {\frac{1}{{48}}} \right).$ Then $\mathop {\lim }\limits_{x \to 2} \int\limits_6^{f(x)} {\frac{{4{t^3}}}{{x - 2}}} dt$ equals

Answer

b
(b) $\mathop {\lim }\limits_{x \to 2} \frac{{\int\limits_6^{f(x)} {4{t^3}dt} }}{{x - 2}}\,\,(0/0\,{\rm{\,\, form}}) = \mathop {\lim }\limits_{x \to 2} \frac{{4{{(f(x))}^3} \times f'(x)}}{1}$

$ = 4{(f(2))^3} \times f'(2) = 18$.

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

Let $a_{1}, a_{2}, a_{3}, \ldots$ be an $A.P.$ If $\sum_{r=1}^{\infty} \frac{a_{r}}{2^{r}}=4$, then $4 a_{2}$ is equal to
A square is inscribed in the circle $x^2+y^2-10 x-6 y+30=0$. One side of this square is parallel to $y=x+3$. If $\left(x_i, y_i\right)$ are the vertices of the square, then $\sum\left(\mathrm{x}_{\mathrm{i}}^2+\mathrm{y}_{\mathrm{i}}^2\right)$ is equal to :
The sum of the series : $(2)^2 + 2(4)^2 + 3(6)^2 + ...$ upto $10$ terms is
The sum of the $3^{rd}$ and the $4^{th}$ terms of a $G.P.$ is $60$ and the product of its first three terms is $1000$. If the first term of this $G.P.$ is positive, then its $7^{th}$ term is
Let $y=f(x)$ be a thrice differentiable function in $(-5,5)$. Let the tangents to the curve $y=f(x)$ at $(1, \mathrm{f}(1))$ and $(3, \mathrm{f}(3))$ make angles $\frac{\pi}{6}$ and $\frac{\pi}{4}$, respectively with positive $x$-axis. If $27 \int_1^3\left(\left(f^{\prime}(t)\right)^2+1\right) f^{\prime \prime}(t) d t=\alpha+\beta \sqrt{3} \quad$ where $\alpha, \quad \beta$ are integers, then the value of $\alpha+\beta$ equals
The value of $6+\log _{\frac{3}{2}}\left(\frac{1}{3 \sqrt{2}} \sqrt{4-\frac{1}{3 \sqrt{2}} \sqrt{4-\frac{1}{3 \sqrt{2}} \sqrt{4-\frac{1}{3 \sqrt{2}} \ldots}}}\right)$ is
In a triangle $PQR$, let $\overrightarrow{ a }=\overline{ QR }, \overrightarrow{ b }=\overrightarrow{ RP }$ and $\overrightarrow{ c }=\overline{ PQ }$. If $|\vec{a}|=3,|\vec{b}|=4$ and $\frac{\vec{a} \cdot(\vec{c}-\vec{b})}{\overrightarrow{ c } \cdot(\vec{a}-\vec{b})}=\frac{|\vec{a}|}{|\vec{a}|+|\vec{b}|}$, then the value of $|\vec{a} \times \vec{b}|^2$ is. . . . . . . 
Suppose the sequence $a_1, a_2, a_3, \ldots$ is a n arithmetic progression of distinct numbers such that the sequence $a_1, a_2, a_4, a_8, \ldots$ is a geometric progression. The common ratio of the geometric progression is
Five numbers are in $A.P.$, whose sum is $25$ and product is $2520 .$ If one of these five numbers is $-\frac{1}{2},$ then the greatest number amongst them is
If all roots of the equation $x^3 -2ax^2 + 3bx -8$=$0$ are positive, $a$,$b \in R$ , then the minimum value of $b$ is