How do you express x^(4/3) in simplest radical form?

1 Answer
Jul 24, 2015

You raise x to the 4^"th" power, then take the cube root.

Explanation:

When dealing with fractional exponents, it's always useful to remember that the exponent can be written as a product of an integer and of a fraction that has the numerator equal to 1.

In general, this looks like this

a/b = a * 1/b

This is important when dealing with fractional exponents because an exponent that takes the form 1/b, like in the above example, is equivalent to taking the b^"th" root.

x^(1/b) = root(b)(x)

Since, for any x>0, you have (x^a)^b = x^(a * b), you can write

x^(4/3) = x^(4 * 1/3) = (x^4)^(1/3) = color(green)(root(3)(x^4))

SImply put, you need to take the cube root from x raised to the 4^"th" power.

Of course, you can also write

x^(4/3) = x^(1/3*4) = (x^(1/3))^4 = color(green)((root(3)(x))^4