Question

How do you express the complex number in trigonometric form: 3?

Answer 1

`3` is written as `3cos0+isin0` or `3e^(i0)`

Explanation:

A number `a+ib` is written as `rcostheta+irsintheta` or `re^(itheta)` in polar form,

where `r=sqrt(a^2+b^2)` and `tantheta=b/a`

As `3=3+i0`, `r=sqrt(3^2+0^)=sqrt9=3`

and as `tantheta=0/3=0`, `theta=0`

Hence `3` is written as `3cos0+isin0` or `3e^(i0)`