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(6-2i)^2 which is the coefficient of i ?

A.−24

B.−12

C.16

D.24

User Sara Hamad
by
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1 Answer

3 votes

Option A: -24 is the coefficient of i

Step-by-step explanation:

The expression is
(6-2 i)^(2)

To determine the coefficient of i, first we shall find the square of the binomial for the expression
(6-2 i)^(2)

The formula to find the square of the binomial for this expression is given by


(a-b)^(2)=a^(2)-2 a b+b^(2)

where
a=6 and
b=2i

Substituting this value and expanding, we get,


(6-2 i)^(2)=6^(2) -2(6)(2i)+(2i)^(2)

Simplifying the terms, we have,


(6-2 i)^(2)=36-24i-4

Thus, from the above expression the coefficient of i is determined as -24.

Hence, Option A is the correct answer.

User Kenneth Browning
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3.1k points