## Evaluate each expression

Simple patterns, variables, the order of operations, simplification, evaluation, linear equations and graphs, etc.
chiefboo
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Joined: Fri Mar 22, 2013 3:46 pm
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### Evaluate each expression

$4^{2/3}$ x $6^{2/3}$ x $9^{2/3}$

So I understand that I convert the numbers into rational expressions and then multiple them...

$\sqrt[3]{16}$ x $\sqrt[3]{36}$ x $\sqrt[3]{81}$

which simplifies to...

2$\sqrt[3]{2}$ x $\sqrt[3]{36}$ x 3$\sqrt[3]{3}$

which equals 36.

but how do I multiply these numbers without a calculator? lol... Maybe I don't even really need to know, but I'm expecting to take a placement test when I reenter university after severals years of not having to do this stuff and I'm concerned they may expect me to know how to multiply rational expressions without a calculator.

I don't know what this process or procedure is called and I can't find any clear examples in my text book.

stapel_eliz
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To learn how to multiply radicals, try here and here. You'll see that you don't have to try to figure out the values of each of the cube roots; instead, you can multiply the insides and deal only with whole numbers.

jg.allinsymbols
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### Re: Evaluate each expression

Each of the bases can be factored, making simplification much easier. You may not need a calculator in you use the bases in their factored form.

4=2^2
6=2*3
9=3^2

Note that each of the exponentiated bases is to the two-thirds power!