How do you divide ( -7i-3) / ( 9 i -4 )7i39i4 in trigonometric form?

1 Answer
May 22, 2017

sqrt(5626)/97*cis(132.84^o)=-51/97+55/97*i562697cis(132.84o)=5197+5597i

Explanation:

To evaluate the division in trig. Form, first you convert the numerator and denominator to polar form:
The numerator in polar form: -7*i-3=sqrt(58)*cis(-113.20^o)7i3=58cis(113.20o)
The denominator in polar form: 9*i-4=sqrt(97)*cis(113.96^o)9i4=97cis(113.96o)

Then evaluate the division:
(-7i-3)/(9i-4)7i39i4
=(sqrt(58)/sqrt(97))*cis(-113.20^o-113.96^o)=(5897)cis(113.20o113.96o)
=sqrt(5626)/97*cis(132.84^o)=562697cis(132.84o)

Convert back to rectangular form:
=-51/97+55/97*i=5197+5597i