3 years ago

Explain why 21i^2 is equivalent to -21

Mathematics

1 answer:

Citrus2011 [14]3 years ago

6 0

Answer:

Step-by-step explanation:

The imaginary number 'i' is equal to the square root of -1. If you were to square the square root, they both cancel and you get -1.

$21i^2=21(\sqrt{-1} )^2=21(-1)=-21$

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