How do you divide (7-4i)/(3+2i) in trigonometric form?

1 Answer
Mar 2, 2016

sqrt5xxe^(i(alpha-beta), where alpha=tan^-1(-4/7) and beta=tan^-1(2/3)

Explanation:

(a+bi) an be written in as sqrt(a^2+b^2)e^(i(tan^-1(b/a))

Hence, (7-4i)=sqrt(7^2+4^2)(e^(itan^-1(-4/7)))=sqrt65e^(itan^-1(-4/7))

Similarly, (3+2i)=sqrt(3^2+2^2)(e^(itan^-1(2/3)))=sqrt13e^(itan^-1(2/3))

Hence (7-4i)/(3+2i)=(sqrt65e^(itan^-1(-4/7)))/(sqrt13e^(itan^-1(2/3)))

or sqrt5xxe^(i(tan^-1(-4/7))-(tan^-1(2/3))) or

sqrt5xxe^(i(alpha-beta), where alpha=tan^-1(-4/7) and beta=tan^-1(2/3)