## Trigonometry 7th Edition

$1 - i$
$\sqrt{2}$ $cis\frac{7\pi}{4}$ = $\sqrt{2}(cos\frac{7\pi}{4} + isin\frac{7\pi}{4})$ = $\sqrt{2}$ ($\frac{\sqrt{2}}{2} - \frac{\sqrt{2}}{2}i$) = $1 - i$