CALCULUS help! =)

posted by .

find the derivative of f(x)=3x^2-x using the limit definition.

  • CALCULUS help! =) -

    f(x) = 3x^2 - x
    f(x+h) = 3(x+h)^2 - (x+h)
    = 3x^2 + 6xh + 3h^2 - x - h

    dy/dx = lim [ ( f(x+h) - f(x)]/h , as h ----> 0
    = lim (3x^2 + 6xh + 3h^2 - x - h - 3x^2 + x)/h
    = lim (6xh + 3h^2 - h)/h
    = lim 6x + 3h - 1 , as h --->0
    = 6x - 1

    (the h--> 0 should be under the word "lim" in each line)

  • CALCULUS help! =) -

    WOW!! You are such a lifesaver!!!!!!!!!=) ...and also very good at math !

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Calculus derivatives

    f(a) = a + √a (a) Find the derivative of the function using the definition of derivative.
  2. calculus

    Consider the function. f (x) = 5x3 + 3x (a) Compute the derivative at x = 3 using the limit definition. f '(3) = (b) Find an equation of the tangent line. 2
  3. calculus

    find the limit of f'(x) = 1/(√x) using the limit definition of derivative.
  4. calculus

    find the limit of f'(x) = 1/(√x) using the limit definition of derivative as x approaches 0.
  5. math

    find derivative using limit definition: f(x) = x - sqrt(x) so f'(x) = lim h->0 [f(x+h) - f(x)]/h but I keep trying to solve by multiplying by the conjugate but I can't figure it out..there's nothing that can be cancelled or anything …
  6. Calculus

    Find the derivative of the function using the definition of a derivative. F(x)=squareroot(1-3x) Please show work for understanding, thank you! :)
  7. applied calculus

    3. a) Write out the limit definition for the derivative of y = xx. Attempt to solve it. b) Write out the limit definition for the derivative of the inverse trig function from question 2. Attempt to solve it. c) Discuss the value of …
  8. Calculus Help Please!!!

    if f(x)= x+(1/x), find f'(x) using the limit definition of derivative. Please show steps!!! Thank you!!!
  9. Calculus

    1.) Find the derivative of tan (sec x). 2.) Find the derivative if 1/x in four ways, using the limit process, power rule, quotient rule and implicit differentiation. 3.) Show that the derivative of sec^-1 x is 1/(|x|*sqrt(x^2 -1)). …
  10. Calculus

    y = g(x) = cos(x) Can someone show how to estimate g'(pi/2) using the limit definition of the derivative and different values of h. Thanks!

More Similar Questions