Question 754077
Solve for x
a) {{{x^(2/3) -x^(1/3) - 2 = 0}}}
This can be factored just like a normal quadratic equation
{{{(x^(1/3)-2)(x^(1/3)+1)}}} = 0; FOIL this & you can prove it to yourself
Two solutions
{{{x^(1/3)}}} = 2
Cube both sides and you have
x = 8
and
{{{x^(1/3)}}} = -1
cube both sides and you have:
x = -1
:
:
Check this, replace x with 8 and -1 in the original problem
Only x = 8 is a valid solution