Question

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

Answer 1

Follow the normal multiplication rules, and remember that `i^2=-1`

Explanation:

`=2*2+2*3i+i*2+i*3i`
`=4+6i+2i+3i^2`
`=4+8i+3*(-1)`
`=1+8i`