If f(r) = r^2, then _ h 0 f(r + h) - f(r) h = - Vidyadip

MCQ

If $f(r) = \pi {r^2}$, then $\mathop {\lim }\limits_{h \to 0} \frac{{f(r + h) - f(r)}}{h} = $

A
$\pi {r^2}$
✓
$2\pi r$
C
$2\pi $
D
$2\pi {r^2}$

✓

Answer

Correct option: B.

$2\pi r$

b
(b)$\frac{d}{{dr}}f(r) = 2\pi r$.

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