Posted by Sam on Monday, May 21, 2012 at 9:27am.
I am not sure what to do here:
Find the derivative (f '(x) using the limit process
a). f(x)= 2x^2+5x+2 find f ' (2)
b.) Find the equation of the Tangent Line at (1,5)

Calculus  Steve, Monday, May 21, 2012 at 10:21am
suppressing the limit notation for the moment,
f' = [f(x+h)f(x)]/h
f' = [(2(x+h)^2 + 5(x+h) + 2)  (2x^2 + 5x + 2)]/h
f' = [(2x^2 + 4xh + 2h^2) + (5x + 5h) + 2  (2x^2 + 5x + 2)]/h
f' = (4xh + 2h^2 + 5h)/h
f' = 4x + 5 + 2h
lim as h>0 = 4x+5

f'(1) = 9
(y5) = 9(x1)

Calculus  Sam, Monday, May 21, 2012 at 10:43am
Thank you so so much! I finally understand what to do! :)
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