radicals and rational exponents. simplifying $4^{5/3}$

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This question is not for homework.

The book says:

$$4^{5/3} = (\sqrt4)^5 = (\sqrt{2^2})^5 = 2^5 = 32$$

when a bunch of us tried it:

$$4^{5/3} = \sqrt[3]{4^5} = \sqrt[3]{2^3 \cdot 2^2} = 2 \cdot \sqrt[3]{2^2} = 2 \cdot \sqrt[3]{4}$$

I get the sense we missed something. Where did we mess it up? We don't know how to get to 32.

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There is probably a typo in your book, since $$(\sqrt 4)^5 = 4^{5/2}\neq 4^{5/3}.$$

However, you still made a mistake in your calculation. You replaced $4^5$ with $2^3\cdot 2^2$, when in reality, $4^5 = 4^3\cdot 4^2 = 2^6 \cdot 2^4$.

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Your book is wrong. $$4^{5/3}\neq (\sqrt4)^5$$