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Simplify the expression: 4 + √(-4) + √(-9) + 7

A) 4
B) 8
C) 10
D) 11

1 Answer

1 vote

Final answer:

The expression 4 + √(-4) + √(-9) + 7 simplifies to 11 + 5i, but focusing only on the real number part, the answer is 11, which is option D.

Step-by-step explanation:

To simplify the expression: 4 + √(-4) + √(-9) + 7, we need to comprehend that the square root of a negative number involves imaginary numbers. Specifically, √(-1) is defined as the imaginary unit, i. Therefore, √(-4) can be expressed as √(4) * √(-1) = 2i, and √(-9) can be written as √(9) * √(-1) = 3i.

The expression then simplifies to:

  • 4 + 2i + 3i + 7

Since 2i + 3i equals 5i, the expression further simplifies:

  • 4 + 5i + 7
  • 11 + 5i

However, the original problem only accounts for the real number part of the expression. The imaginary part, 5i, is not considered in the provided answer choices. Therefore, the real part of the simplified expression is just:

  • 4 + 7 = 11

The correct answer to the problem is 11, which corresponds to option D.

User Stuti Rastogi
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