Evaluate a limit by factoring to resolve a 0/0 form
Consider the function .
Find
Hint
Direct substitution gives . Factor the numerator as a difference of cubes and the denominator as a difference of squares, then cancel the common factor before substituting.
Step-by-step solution
Substituting directly gives , an indeterminate form, so we cannot use direct substitution and must simplify algebraically first. Factor the numerator using the difference of cubes formula: . Factor the denominator using the difference of squares formula: .
Since as , the common factor can be canceled, giving Now apply the quotient rule for limits, since both numerator and denominator have finite limits with a nonzero denominator limit at :
Related problems
Practice similar Calculus problems interactively.
Start Closing the Gap