Question

Please help!!Which of the following expressions are equivalent to (2+i)^2 where i is the imaginary number:
I. (-2-i)^2
II. 3+4i
III. 3


a. I only
b. II only
c. III only
d. I and II only
e. I and III only

Answer 1

\[(2+i)^2=(2+i)(2+i)=(4-1)+(2+2)i=3+4i\]

Answer 2

so II is good

Answer 3

try and see if you get the same with \((-2-i)^2\)

Answer 4

okay thank you :)

Answer 5

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