#10

Read 3.4

• Prob A.  If f(x)=x, prove f '(x)=1 by definition of derivative.
  
  
• Prob B.  If f(x)=x⁴, prove f '(x)=4x³ by definition of derivative (expand (x+h)⁴).
  

3.4; 1, 15+, 17+, 38, 39, 55.
On 15 and 17, in addition to everything instructed, after you prove the derivative formula, use it to find the equation of the tangent line to the curve at x=3.