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What is the simplified form of $\left\{(x^m)^{\frac{1}{m}}\right\}^{\frac{1}{m+1}}$?

A$x^{m-1}$
B$x^{\frac{1}{m+1}}$
C$x^{\frac{1}{m(m+1)}}$
D$x$
Answer & Solution
Correct answer: C. $x^{\frac{1}{m(m+1)}}$
**Use the power law repeatedly:** $(a^p)^q=a^{pq}$. Here, $\left\{(x^m)^{1/m}\right\}^{1/(m+1)}=x^{m\cdot \frac{1}{m}\cdot \frac{1}{m+1}}=x^{1/(m+1)}$. **Wait carefully:** after simplifying $(x^m)^{1/m}=x$, raising that to $1/(m+1)$ gives $x^{1/(m+1)}$. So the correct answer is B if the expression is read exactly as printed. The source solution appears to correspond to a different expression. **Hence the mathematically correct simplification is $x^{1/(m+1)}$.**
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