Skip to main content

Math Trailhead

Worksheet Radicals and Rational Exponents

6.

Compute the following. Use "undefined" or "imaginary" for non-real results.
\(\large{32^{4/5}}\) =
Hint.
Remember that fractions as exponents can be translated into radical form.
\(\large x^{m/n} = \left(\sqrt[n]{x}\right)^m\)
Answer.
Solution.
Rewrite the fractional exponent as a radical:
\(\displaystyle 32^{4/5} = \left(\sqrt[5]{32}\right)^{4}\)
Compute the radical:
\(\displaystyle \left(\sqrt[5]{32}\right)^{4} = (2)^{4}\)
Compute the exponent:
\(\displaystyle (2)^{4} = 16\)

12.

Simplify the following expression. Write your answer using positive exponents only.
\(\large{z^{1/2} z^{1/2}}\) =
Hint.
Recall the property of exponents:
\(\displaystyle B^m \cdot B^n = B^{(m+n)}\)
Remember that negative exponents can be rewritten with positive exponents.
\(\displaystyle B^{-n} = \frac{1}{B^n}\)
Answer.
Solution.
Use the property of exponents:
\(\displaystyle z^{1/2} z^{1/2} = z^{((1/2)+(1/2))}\)
Off to the side, add the exponents:
\(\displaystyle \frac{1}{2} + \frac{1}{2} = \frac{2}{2}\)
so now we have \(\displaystyle z^{((1/2)+(1/2))} = z^{2/2}\)
Simplify your answer:
\(\displaystyle z^{2/2} = z\)