Fundamental Theorem of Calculus application for $f(x)geq 0$

Can anybody help me with how to solve the following question using the fundamental theorem of calculus? I’m a bit confused…

Suppose that $f$ is a continuous function on $[a, b]$ and that $f(x)geq 0$ for all $xin [a, b]$. Show that if $intlimits_a^b f(x)dx = 0$ then $f(x) = 0$ for all $xin [a, b]$.