Question
The value of $c$ in Rolle's theorem for the function $f(x) = {x^3} - 3x$ in the interval $[0,\sqrt 3 ]$ is
- (a) 1 ✓ Correct
- (b) -1
- (c) $\frac{3}{2}$
- (d) $\frac{1}{3}$
The value of $c$ in Rolle's theorem for the function $f(x) = {x^3} - 3x$ in the interval $[0,\sqrt 3 ]$ is
$\Rightarrow$ $\quad 3{c^2} - 3 = 0$
$\Rightarrow$ ${c^2} = \frac{3}{3} = 1$
$\Rightarrow$ $c = \pm 1,$ where $1 \in (0,\sqrt 3 )$
therefore,$\quad c = 1$
NCERT & Exemplar solution for CBSE Class 12 Mathematics, Continuity and Differentiability. Curated by Sachin Sharma. Free for all students.