Evaluate a definite integral of an exponential function using FTC Part 2

An antiderivative of $f(x) = e^x$ is $F(x) = e^x$, since $\frac{d}{dx}[e^x] = e^x$. By the Fundamental Theorem of Calculus, Part 2, $\int_0^{\ln 2} e^x\,dx = F(\ln 2) - F(0) = e^x\Big|_0^{\ln 2}$.

Substituting the limits gives $e^{\ln 2} - e^0$. Since $e^{\ln 2} = 2$ and $e^0 = 1$, the value of the integral is $2 - 1 = 1$.