Question

Solve this equation by using the quadratic form.

x^4 - 144 = 0

Answer 1

Substitute \[u=x^2\] and solve via quadratic formula, then undo substitution and solve again

Answer 2

Hint: Start off by factoring the equation through "Difference of Squares":\[\bf x^4-144=0 \implies x^4-12^2=0 \implies (x^2)^2-12^2=0\]

Answer 3

Note that the difference of squares for \(a\) and \(b\) is: \(a^2-b^2=(a-b)(a+b)\).
After factoring, equate each factor with 0 and solve for x.