Evaluate lim as x approaches a for (x^1/3 - a^1/3)/(x-a). I want to factor out x-a from the numerator so that the denominator is not equal to zero. How can I do this?
Answers and Replies
Related Calculus and Beyond Homework Help News on Phys.org
Another way to do that (Dick's hint is perfectly good) is not to factor but to multiply to rationalize the numerator. Using the same formula Dick gave, x- a= (x^{1/3}- a^{1/3})(x^{2/3}+ a^{1/3}x^{1/3}+ a^{2/3}). Multiply both numerator and denominator by that.