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42 votes
Which expression is equivalent to 3
5v ?

Which expression is equivalent to 3 5v ?-example-1
User Blaine
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1 Answer

17 votes
17 votes

Answer:

x ^5/3 y ^1/3 (the second option listed)

Explanation:

So without even solving the expression, you can find the correct option. If you're finding the cube root (or really any square root), you know it will be less than your original number (unless you are working with imaginary numbers, but you aren't).

So, if you are finding the cube root of an expression, you're finding the cube root of each number separately.

You wouldn't be cubing y, you would be finding the cube root. You wouldn't be leaving y the same, you are finding the cube root.

This means that without even solving (which I will explain),

the correct option is the second one on the screen.

Here's how to actually solve the equation:

So, if we are finding the cube root of a variable with an exponent, we can divide that exponent by 3 (because it is a cube root).

When we have a square root, you know that we are breaking down each number/variable into an even exponent to solve the expression. When taking the square root of an even exponent, such as 4, you would divide by 2.

This same strategy applies to cube roots. You are dividing the exponent of both variables by 3.

[remember: the exponent of a variable without an exponent is essentially an invisible exponent of 1.]

User Atamanroman
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