simplify (x²-1)∧-2/3
(x² - 1)^-2/3∛(x² - 1)-²∛(1/(x² - 1)(x² - 1))∛(1/(x^4 - x² - x² + 1))∛(1/(x^4 - 2x² + 1))1/x^4/3 - 1.25992105x^2/3 + 1