## Calculus (3rd Edition)

$\Delta f= 0.12$
$\Delta f= f(a+\Delta x)-f(a)=f(3.02)-f(3)$ $\implies a=3$ and $\Delta x= 0.02$ According to the Eq.2, $\Delta f= f'(a)\Delta x= f'(3)\times0.02$ $= 2\times3\times0.02= 0.12$