Advanced algebraic concepts including polynomials, rational expressions, and complex numbers.
Once you've solved a problem, always substitute your answer back into the original equation or inequality to see if it works. This helps catch careless errors and builds confidence in your answer. For rational expressions, double-check that you didn't use a value that makes the denominator zero!
Plugging \( x = 2 \) back into \( x^2 - 4 = 0 \) to verify the solution.
Reviewing your steps in a long division problem to find mistakes before moving on.