A community for students.

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

anonymous

  • 4 years ago

Please help on this problem Let f(x) = x-x^3 to determine the approximate slope of the line tangent to the graph of f at (a, f (a)). a = -0.2 slope= ? & a = 0.6 slope=? thanks

  • This Question is Closed
  1. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    I am really lost

  2. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    0.88 was wrong for some reason

  3. dumbcow
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    oh ok well the derivative of f(x) is 1-3x^2

  4. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    can you show me step by step?

  5. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    a= 0.6 then the slope is ?

  6. dumbcow
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    yeah its called the power rule d/dx x^n = n*x^(n-1) so for x x^1 -> 1*x^0 = 1 for x^3 x^3 --> 3*x^2

  7. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    could you do the same for question part b?

  8. dumbcow
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    are you sure its not 0.88 ??

  9. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    i'll plug it in again to be sure

  10. dumbcow
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    1-3(-.2)^2 = 0.88

  11. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    I plugged it in and its right for a=-0.2

  12. dumbcow
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    for part b) its the same derivative function, you are just evaluating the slope at x=0.6 --> 1-3(.6)^2

  13. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    ok hold on for sec let me work it out before you tell me the anwser lol

  14. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    I got -0.72 is that right?

  15. dumbcow
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    nope

  16. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    awww

  17. dumbcow
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    multiply before you add

  18. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    -0.08?

  19. dumbcow
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    i think you did 1-3 = -2 * .36 ?? multiply 3*.36 first

  20. dumbcow
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    yes :)

  21. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    yeahhhh! lol

  22. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    so the derivitive would be 1-3(x)^2 for this problem only?

  23. dumbcow
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    yes only for the function x-x^3

  24. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    ok thanks alot

  25. Not the answer you are looking for?
    Search for more explanations.

    • Attachments:

Ask your own question

Sign Up
Find more explanations on OpenStudy
Privacy Policy

Your question is ready. Sign up for free to start getting answers.

spraguer (Moderator)
5 → View Detailed Profile

is replying to Can someone tell me what button the professor is hitting...

23

  • Teamwork 19 Teammate
  • Problem Solving 19 Hero
  • You have blocked this person.
  • ✔ You're a fan Checking fan status...

Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.

This is the testimonial you wrote.
You haven't written a testimonial for Owlfred.