Find the product 5i 2 i2 5i 2 i2 Type your answer in the fo

Find the product. 5i (2- i)^2 5i (2- i)^2 = (Type your answer in the form a + b i.)

Solution

Given 5i(2-i)².

Need to find the product.

5i(2-i)² = 5i *[ 2²+i²- 2(2)(i) ]

= 5i *[4 -1 -4i] (i² = -1)

= 5i* [3 - 4i]

= 5i*3 - 5i*4i

= 15i - 20i²

= 15i - 20 (-1)

= 15i + 20

= 20 +15i

Therefore, 5i(2-i)² = 20 +15i