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
ab=a⋅1b
This is important when dealing with fractional exponents because an exponent that takes the form 1b, like in the above example, is equivalent to taking the bth root.
x1b=b√x
Since, for any x>0, you have (xa)b=xa⋅b, you can write
x43=x4⋅13=(x4)13=3√x4
SImply put, you need to take the cube root from x raised to the 4th power.
Of course, you can also write
x43=x13⋅4=(x13)4=(3√x)4