# What is the trigonometric form of #5+6i#?

##### 1 Answer

Feb 28, 2016

#### Explanation:

using the following formulae.

#• r^2 = x^2 + y^2#

#• theta = tan^-1 (y/x)# here x = 5 and y = 6

#r^2 = 5^2+6^2 = 25+36 = 61 rArr r = sqrt61#

#theta = tan^-1(6/5) ≈ 0.876 " radians "# hence the trig. form of 5 + 6i is:

#sqrt61[ cos(0.876) + isin(0.876)]#