# How do you express the complex number in trigonometric form: -1+i?

$- 1 + i = \sqrt{2} \cdot \left(- \frac{\sqrt{2}}{2} + \frac{\sqrt{2}}{2} \cdot i\right) = \sqrt{2} \cdot \left(\cos \left(\frac{3 \pi}{4}\right) + i \cdot \sin \left(\frac{3 \pi}{4}\right)\right)$