Explain in one sentence why

MATHEMATICS · Subjective · AP · Calculus AB · Integration and Accumulation of Change · Integration and Accumulation of Change

Problem

Explain in one sentence why, for a continuous function

f

and differentiable function

g,

the derivative of

F(x)=\int_{a}^{g(x)} f(t)\,dt

equals

f(g(x))\,g'(x).