alleryStart learning →Taking √−4 = 2i and √−9 = 3i, what is the product √−4 × √−9?
A±6
B36
C−6
D6
Answer & Solution
Correct answer: C. −6
The product is 2i · 3i = 6i² = −6, not 6, because √a·√b = √(ab) fails when both a and b are negative.
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