How do you write the complex number $- 3 + 4 i$ $-3+4i$ in polar form?

Question

26896 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2016-11-15T10:27:20

The polar form is $=5(cos126.9º+isin126.9º)$

Let $z=a+ib$ a complex number

The polar form is $z=r(costheta+isintheta)$

$r=sqrt(a^2+b^2)$

Here, we have $z=-3+4i$

$:.r=sqrt(9+16)=sqrt25=5$

$z=5(-3/5+(4i)/5)$

$:.cos theta=-3/5$ and $sintheta=4/5$

So, $theta$ is in the second quadrant

$theta=126.9$ º

$z=5(cos126.9º+isin126.9º)$

How do you write the complex number -3+4i−3+4i-3+4i in polar form?