Problem 115 of 7
Explain why sqrt(-16) requires complex numbers.
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reason that real squares are nonnegative.
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Number must be negative.
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Solution
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1. Recall that any real number squared is nonnegative.
2. A negative radicand cannot have a real square root.
3. Introduce i to represent sqrt(-1) and write the complex value.
Use the worked steps, then substitute the final answer back into the original relationship to confirm it satisfies the prompt.
Saying the expression is undefined without mentioning complex numbers.