Critical Point Definition
At x=c
when f’(c)=0 or f’(c) does not exist
Local Extrema Definition
Just when the graph reaches it max or min point
Second Derivative Test
If f’‘(c)>0, then local minima at c, concave up
If f’‘(c)<0, then local maxima at c, concave down
Taylor Series
It’s an approximation
f(0)+f’(0)/1!x + f’‘(0)/2!x^2 …