# Math Help - Complex numbers

1. ## Complex numbers

How can I change polar coordinates z=7(cos(5pi/3)+isin(5pi/3)) into binomial form?

2. ## Re: Complex numbers

Hey franios.

What do you mean by binomial form? Is this something like (a+b)^n? What you can do is use z = re^(it) where t = 5pi/3 and then you can use the fact that e^(i5pi/3) = (e^(ipi/3))^5 which means (cos(pi/3) + isin(pi/3))^5 = (cos(5pi/3) + isin(5pi/3)).

3. ## Re: Complex numbers

Originally Posted by franios
How can I change polar coordinates z=7(cos(5pi/3)+isin(5pi/3)) into binomial form?
It is almost in Binomial form as it is, just multiply through by 7 and evaluate the given trigonometric functions...