How does factoring and cancelling resolve the indeterminate limit of ()/() as x approaches 2?
Conditions
- The limit is as .
- The original expression is undefined at (indeterminate form ).
- Cancellation is valid only for .
Reasoning, step by step
- Identify the indeterminate form by substituting into the original expression.
- Factor the numerator into .
- Factor the denominator into .
- Cancel the common factor from the numerator and denominator, noting that this is valid for .
- Evaluate the limit of the simplified expression as by direct substitution.
- Calculate the final value: .
Example
The script states: "For near 2, . Its limit as is ."
Common misconceptions
- Believing that cancelling factors changes the value of the function at the point .
- Thinking that the limit does not exist because the original function is undefined at .
- Confusing the simplified function with the original function globally, rather than just near the limit point.
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