Question

Given the expression (1 + 2i)2, perform the indicated operation and write the answer in the form a + bi.

−1 − 2i
−3 + 4i
−4 − 4i
−3 − 4i

Answer 1

yes they are.

Answer 2

@iGreen help pls

Answer 3

(1 + 2i)(1 + 2i)
= (1 + 2i) + 2i(1 + 2i)
can you continue?

Answer 4

distribute 2i over (1 + 2i)

Answer 5

= 1 + 21 + 2i*1 + 2i*2i
= ?

Answer 6

8 sorry that's 1 + 2i + 2i*1 + 2i*2i

Answer 7

what is 2i* 2i?

Answer 8

no its 4i^2

do you know what the definition of i is?

Answer 9

when you manipulate it algebraically just treat it as a variable like x or y.

Answer 10

its an imaginary number and equal to sqrt(-1)
so i^2 = sqrt(-1) squared = -4
so 4i^2 = -4

Answer 11

gotta go right now