Question

express the following in the form a+ib:[(1+2i)÷(2+i)]^2​

Answer 1

Answer:

[4/5+3i/5]^2

Step-by-step explanation:

[1+2i/2+i]^2  calculate the value inside the square bracket

1+2i/2+i ......... multiply both numerator and denominator with 2-i.

we will get...

2-i+4i+2/4-2i+2i+1 .........where 2i will get canceled

........

4+3i/5 i.e 4/5+3i/5 .......add square and don't calculate it further by squaring it cuz as per the question we should get in the form of a+ib..

[4/5+3i/5]^2