Part 1: The derivative at a specific point

Use the definition of the derviative to compute the derivative of [math] at the specific point [math]. Evaluate the limit by using algebra to simplify the difference quotient (in first answer box) and then evaluating the limit (in the second answer box).
[math] [math] .
Hint: use the conjugate trick.

Part 2: The derivative function

Part 3: The tangent line