## Calculus 8th Edition

$-\frac{5}{4}$
We use the derivative formula for $sec \theta$ $$\frac{d}{dx} sec \theta = sec \theta tan\theta$$ to evaluate the given integrand Now, we substitute $\frac{\pi}{4}$ and $0$ into $\theta$ and get $sec(\frac{\pi}{4}) - sec0 =$ $-\frac{1}{4} - 1 = -\frac{5}{4}$