Evaluating a limit by factoring to remove a 0/0 form
Consider the function Note that direct substitution of gives the indeterminate form . Factor the numerator, cancel the common factor with the denominator, and then use the limit laws to evaluate
Hint
Factor into two binomials. One of them should match the denominator, allowing you to simplify the expression before substituting .
Step-by-step solution
Since substituting directly gives , an algebraic simplification is needed. Factor the numerator: . This shows the numerator and denominator share a common factor of .
For , we can cancel the common factor to write . Since this simplified expression is a polynomial (continuous everywhere), the quotient and sum rules justify evaluating the limit by direct substitution: .
Identifying the simplified linear expression after cancellation
Hint
Step-by-step solution
After factoring the numerator and canceling the common factor of x minus two, the expression simplified to x plus five. This linear expression is continuous everywhere, so direct substitution of x equals two could then be applied. The cancellation step is what removed the original zero over zero indeterminate form.
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