Calculus

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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 -

    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

    (y-5) = 9(x-1)

  • Calculus -

    Thank you so so much! I finally understand what to do! :)

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