If you tried to solve the limit with substitution and it didn’t work, factoring should be the next thing you try. The goal will be to factor the function, and then cancel any removable discontinuities, in order to simplify the function, so that it can be evaluated.

Read MoreTo add rational expressions, you need to find a common denominator, just like when you add fractions in which the numerator and denominator are just numbers. The difference is that finding the common denominator of rational expressions can be more complicated because their denominators can include variables.

Read MoreThe zero theorem allows you to solve for the roots of a polynomial function. Just factor the polynomial, set it equal to 0, and solve for the variable to find the roots.

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