Question
Find the derivative of
$\left(5 x^{3}+3 x-1\right)(x-1)$

Answer

Let $f(x)=\left(5 x^3+3 x-1\right)(x-1)$
By product rule of differentiation,we have,
$f^{\prime}(x)=\left(5 x^3+3 x-1\right) \frac{d}{d x}(x-1)+(x-1) \frac{d}{d x}\left(5 x^3+3 x+1\right)$
$=\left(5 x^3+3 x-1\right) \times 1+(x-1) \times\left(15 x^2+3\right)$
$=\left(5 x^3+3 x-1\right)+(x-1) \times\left(15 x^2+3\right)$
$=5 x^3+3 x-1+15 x^3+3 x-15 x^2-3$
$=20 x^3-15 x^2+6 x-4$

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