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Find the conjugate of 2 - 5i and then calculate the product of the given complex

number and its conjugate. (1 point)
O The conjugate is –2 + 5i and the product is -4 - 201 - 2522.
The conjugate is 2 + 5i and the product is 4 -
2522
O The conjugate is -2 + 5i and the product is - 29.
The conjugate is 2 + 5i and the product is 29.
JUST ONE MORE !! PLS

User Tibor
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2 Answers

5 votes
Okay yes but t is 29 and I hopes this helps good luck
User Raveturned
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1 vote

Answer:

The conjugate is 2+5i and the product is 29.

Explanation:

The conjugate of a complex number
a+bi is
a-bi

Our complex number is 2-5i.

Here, a = 2 and b = -5

Thus, the conjugate of 2-5i is


2-(-5i)=2+5i

Using this rule:


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

And the fact that
i^(2) = -1

We can find the product of any complex number and its conjugate:


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

As our complex number is
2-5i, the product with its conjugate will be


2^(2) + (-5)^(2) =4+25=29

User Nazia Jan
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