2.8.1
By definition of the derivative,
We have
and
Combine these fractions into one with a common denominator:
Rationalize the numerator by multiplying uniformly by the conjugate of the numerator, and simplify the result:
Now divide this by <em>h</em> and take the limit as <em>h</em> approaches 0 :
3.1.1.
Differentiate one term at a time:
• power rule
The last two terms are constant, so their derivatives are both zero.
So you end up with