Q. Given x>0 and y>0, select the expression that is equivalent to−100x7y1510ix27y215−10x27y21510ix14y30−10x14y30
Rewrite using imaginary unit: We are given the expression −100x7y15. The square root of a negative number involves the imaginary unit i, where i2=−1. Therefore, we can rewrite the expression as −1×100x7y15.
Factor out terms: The square root of −1 is the imaginary unit i, and the square root of 100 is 10. We can then factor out these terms to get 10i⋅x7y15.
Express exponents as squares: Next, we can express x(7) as x(7/2)2 and y(15) as y(15/2)2 to prepare them to be taken out of the square root, since a2=a.
Take square roots: Taking the square root of x(7/2)2 and y(15/2)2, we get x7/2 and y15/2 respectively. Therefore, the expression becomes 10i×x7/2×y15/2.
Final expression: The final expression is 10i×x27×y215, which is equivalent to the given expression −100x7y15.
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