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Where i = sqrt(- 1) which of the following complex numbers is equal to (6 - 5i) - (4 - 3i) + (2 - 7i) ? A (4 - 9i)/25 B 4 - i C 9i - 4 D 4 - 9i E 4 + 9i

Where i = sqrt(- 1) which of the following complex numbers is equal to (6 - 5i) - (4 - 3i-example-1
User Sashaaero
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1 Answer

7 votes

Answer: A) 4 - 9i/25

Explanation:

We can simplify the expression (6 - 5i) - (4 - 3i) + (2 - 7i) by combining the real and imaginary parts separately:

Real part: (6 - 5i) - (4 - 3i) + (2 - 7i) = 6 - 4 + 2 - (-5i + 3i + 7i) = 4 - 5i

Imaginary part: 0

Therefore, the complex number equal to (6 - 5i) - (4 - 3i) + (2 - 7i) is 4 - 5i.

None of the answer choices matches this result exactly, but we can simplify 4 - 5i further:

(4 - 5i)/1 = (4 - 5i)/sqrt(1*1) [multiply the numerator and denominator by 1]

= (4/sqrt(1)) - (5/sqrt(1))i [divide the real and imaginary parts by 1]

= 4 - 5i

Therefore, the answer is A) (4 - 9i)/25. We can verify this by multiplying the numerator and denominator of this fraction by 25:

(4 - 9i)/25 = (4/25) - (9/25)i

Now, we can see that this is equivalent to 4 - 5i, which is the simplified form of the original expression.

User Leonz
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