96.5k views
2 votes
Can someone PLEASE explain how to simplify square roots with variables and eexponents in them?? I'd also be thankful if you explained step-by-step how to

solve (16x^4)^3/2 and how to simplify 3y^4/3 times 3yx^1/2? I have to do a retake on my math test and I REALLY need help!

1 Answer

3 votes
x^a/b is
\sqrt[b]{x^a} . The way I memorise that is x^1/3 is the cubic root of x. Do you get it? In that case, x is raised to a power of 1 and the cubic root is practically has a power of 3.
In your example,


\sqrt[ (3)/(2) ]{16 x^4} is practically square rooting each term then cubing them individually. Remember when square-rooting any index you halve it. I'll elaborate:


√(x^4) =
x^(2)

√(16) = 4
Then cube each,

4^3 = 64
and
( x^(2) )^3 =
x^(6)

As for the 2nd part: you must use the rules of indices.

x^(a) * x^(b) = x^(a+b)
So breaking the question up:

3 * 3 = 9

x^{ (1)/(2) } stays as is since the 2nd term does not contain x
now:

y^{ (4)/(3) } * y^(1) = y^{ (4)/(3) + 1 } = y^{ (4)/(3) + (3)/(3) } = y^{ (7)/(3) }
This makes your final answer look like this:

9 x^{ (1)/(2) } y^{ (7)/(3) }

I hope that helped and good luck in your test!
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories