Originally Posted by

**Paymemoney** Hi

I need help on the following two questions:

1)Differentiate with respect with x: $\displaystyle \frac{1}{(7x^2+3)^5}$

This is what i have done, not sure if i have done it correctly:

using quotient rule

$\displaystyle \frac{(7x^2+3)^5 * 0- 1 * 5(7x^2+3)^4 * 14x}{((7x^2+3)^5)^2}$

$\displaystyle \frac{-70x(7x^2+3)^4}{(7x^2+3)^6}$

$\displaystyle \frac{-70x}{(7x^2+3)^6}$

2)Differentiate with respect with x: $\displaystyle (2x-1)^4 * (x+5)^{\frac{1}{2}}$

using the product rule

$\displaystyle (2x-1)^4 * \frac{1}{2}(x+5)^{\frac{1}{2}} + (x+5)^{\frac{1}{2}} * 4(2x-1)^3 * 2$

$\displaystyle \frac{2(2x-1)^4}{\sqrt{x+5}} + \frac{8(2x-1)^3 * (x+5)^{\frac{1}{2}}}{\sqrt{x+5}}$

What would i do next?

P.S