How do you simplify (4+ 2i) /( -1 + i)4+2i1+i?

1 Answer
May 2, 2018

(4+2i)/(-1+i) | *(-1-i)4+2i1+i(1i)

((4+2i)(-1-i))/((-1+i)(-1-i))(4+2i)(1i)(1+i)(1i)

(-2i^2-6i-4)/(1-i^2)2i26i41i2

(2-6i-4)/(1+1)26i41+1

(-2-6i)/(2)26i2

=-1-3i=13i

Explanation:

We want to get rid of ii in the the bottom of the fraction in order to get it on Certesian form. We can do this by multiplying with (-1-i)(1i).

This will give us,

((4+2i)(-1-i))/((-1+i)(-1-i))(4+2i)(1i)(1+i)(1i)

(-2i^2-6i-4)/(1-i^2)2i26i41i2

Out from here we know that i^2=-1i2=1 and -i^2=1i2=1. So we can get rid of the i^2i2 too. Leaving us to

(-2-6i)/(2)26i2

=-1-3i=13i