Question

F(x)= 3senx-8cosx+20lnx

Answer 1

lembrando que as derivadas
$\bmatrix sen(u) ' = cos(u)*u'\\\\cos(u)'=-sen(u)*u'\\\\ln(u)'= \frac{1}{u}*u' \end$

$f(x)=3*sen(x)-8*cos(x)+20*ln(x)\\\\f'(x)=3*cos(x)-8*(-sen(x)) + 20 *\frac{1}{x} \\\\ f'(x)=3cos(x)+8sen(x)+ \frac{20}{x}$