What is the limit definition of a derivative and how is it used?
Conditions
- A finite real derivative limit must exist at the point.
- The point is interior and while taking the limit.
Reasoning, step by step
- Form the difference quotient using a nonzero increment Δx.
- Take the limit as Δx approaches zero.
- Evaluate the resulting finite real limit to find the derivative and tangent slope.
Example
The source recalls the formula to define the derivative at an interior point.
Common misconceptions
- Thinking the source proves the power rule from this definition; the material explicitly states it does not prove the power rule from it.
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