Question

What is the product of (1 + i)(2 + i)?

Answer 1

The product of given expression is (1+3i).

Explanation:

The given expression is

`(1+i)(2+i)`

Using distributive property of multiplication, we get

`1(2+i)+i(2+i)`

Using distributive property of multiplication again.

`2+i+i(2)+i(i)`

`2+i+2i+i^2`

`2+i+2i-1`
`[\because i^2=-1]`

Combine like terms.

`(2-1)+(i+2i)`

`1+3i`

Therefore the product of given expression is (1+3i).

Answer 2

(1+i)(2+i)

2+1i+2i-1

your answer: [1 + 3i]

hope this helps