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#