If y=a x^2+b, then d y d x at x=2 is equal to - Vidyadip

MCQ

If $y=a x^2+b$, then $\frac{d y}{d x}$ at $x=2$ is equal to

✓
$4 a$
B
$3 a$
C
$2 a$
D
none of these

✓

Answer

Correct option: A.

$4 a$

We have, $y=a x^2+b$
$\Rightarrow \frac{d y}{d x}=2 a x$
$\left.\frac{d y}{d x}\right|_{x=2}=2 a \times 2=4 a$

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