Question

4) Express the following in the form of a+ib,

a, b∈R i = −1. State the values of a and b.

i) (1+2i)(−2+i)

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Answer 1

Answer:

the ans is 3

Step-by-step explanation:

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

As given i = -1

=> (1+ 2(-1)) ( -2 + (-1))

=> (1 -2 )(-2 -1)

=> (-1) (-3) = 3

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