How do you divide (-3+5i)/(2-i) 3+5i2i in trigonometric form?

1 Answer
Aug 15, 2017

(-3+5i)/(2-i) = 1/5sqrt (170)(cos2.57+isin2.57)3+5i2i=15170(cos2.57+isin2.57)

Explanation:

(-3+5i)/(2-i)=((-3+5i)(2+i))/((2-i)(2+i))= (-11+7i)/5 = -11/5+7/5i3+5i2i=(3+5i)(2+i)(2i)(2+i)=11+7i5=115+75i

Use mod-arg form, a+bi=r(cosvartheta+isinvartheta)a+bi=r(cosϑ+isinϑ) where r= sqrt (-11/5^2+7/5^2) = sqrt (34/5) = 1/5sqrt170r=1152+752=345=15170 and vartheta = arctan ((7/5)/(-11/5))+pi = 2.57^"c"ϑ=arctan(75115)+π=2.57c