Bunuel wrote:

Which of the following expressions is equivalent to \((s^2 + 9)^{(-\frac{1}{2})}\) ?

A. \(-\frac{s^2 + 9}{2}\)

B. \(-\frac{1}{\sqrt{s^2 + 9}}\)

C. \(-\sqrt{s^2 + 9}\)

D. \(\frac{1}{s+3}\)

E. \(\frac{1}{\sqrt{s^2 + 9}}\)

As the calculation we're asked to do is straightforward, we'll just do it.

This is a Precise approach.

A negative power of a number is the reciprocal of that number to the positive power.

A power of 1/2 is the same as a square root. So:

So, \((s^2 + 9)^{(-\frac{1}{2})} = \frac{1}{(s^2 + 9)^{\frac{1}{2}}}\) = \(\frac{1}{\sqrt{s^2 + 9}}\)

(E) is our answer.

_________________

David

Senior tutor at examPAL

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