Differentiate the following.

a$)$ mark$]$

b$)y=5x{e}^x$

$[1$ mark$]$

c$)y=6co{s}^3(2x),[2$ marks$]$

d$)y=sin(x-x^2)-cos(\frac{3}{x})$

$[2$ marks$]$

e$)y=e^{cos(x)}sin(2x-1)$

$[2$ marks$]$

f$)f(x)=cos(7x)-cos(5x)$

$[2$ marks$]$