# What is the trigonometric form of  (7+i) ?

Dec 8, 2015

$5 \sqrt{2} \left(\cos \left(\arctan \left(\frac{1}{7}\right)\right) + i \cdot \sin \left(\arctan \left(\frac{1}{7}\right)\right)\right)$

#### Explanation:

From the diagram above:

$r = \sqrt{{7}^{2} + {1}^{2}} = \sqrt{50} = 5 \sqrt{2}$

$\theta = \arctan \left(\frac{1}{7}\right)$