If i^2 = −1 and x = i + 9, which is the result of squaring x?
1 answer:
Answer:
80 + 18i
Step-by-step explanation:
i² = -1
x = i + 9
x² = (i + 9)²
Applying; (a + b)² = a² + 2ab + b² concept,
x² = i² + 18i + 81
We know that i² = -1
So x² = -1 + 18i + 81
x² = 81 - 1 + 18i = 80 + 18i
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M to the power 4 squared minus 23
To evaluate the expressions, you substitute -9 for x and 3 for y into the expressions
(4y)^2 - (2x)
= (4(3))^2 - (2(-9))
= (12)^2 - (-18)
= 144 + 18
= 162
4y^2 - 2x^2
= 4(3)^2 - 2(-9)^2
= 4(9) - 2(81)
= 36 - 162 = -126
Answer:
B
Step-by-step explanation:
First blank: 8
Second blank: 5
Third blank: 20
Fourth blank: 60
