Question

dada a função f (x) = 3x - 4 calcule a) f (1/3)
b) f (-1)

Answer 1

$\mathsf{f(x)=3x-4}\\\\\\ \mathsf{f\left(\dfrac{1}{3}\right)=3\cdot\dfrac{1}{3}-4}\\\\ \mathsf{f\left(\dfrac{1}{3}\right)=\dfrac{3}{3}-4}\\\\ \mathsf{f\left(\dfrac{1}{3}\right)=1-4}\\\\ \boxed{\mathsf{f\left(\dfrac{1}{3}\right)=-3}}\\\\\\\\ \mathsf{f(-1)=3\cdot(-1)-4}\\\\ \mathsf{f(-1)=-3-4}\\\\ \boxed{\mathsf{f(-1)=-7}}$