Question

How do you simplify `(6-3i)/ (2+i)`?

Answer 1

I found: `9/5-12/5i`

Explanation:

You need to change the denominator into a pure real and then divide. To do this you can multiply and divide by the complex conjugate of the denominator `2-i` to get:

`(6-3i)/(2+i)*(2-i)/(2-i)=`
`=(12-6i-6i+3i^2)/(4+1)=` remembering that `i^2=-1`
`=(12-12i-3)/5=9/5-12/5i`