Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

lovesit2x

  • 3 years ago

Find dx/dy for the following function: y=sinx+5e^.4x dx/dy =

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

    is it dx/dy?

  2. lovesit2x
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    what does dx/dy equals

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

    I just want to make sure the question, because dx/ dy !=dy/dx

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

    if it is dx/ dy. it's not easy to solve. you must solve for x first , then take derivative respect to y.

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

    it will behave implicitly

  6. mathsmind
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    i think she means dy/dx

  7. lovesit2x
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    i thought i had to find the derivative and then solve for y

  8. Hoa
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    @mathsmind you help her, ok?

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

    no u help her

  10. mathsmind
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    can u double check the question plz

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

    it must be dy/dx at ur level

  12. lovesit2x
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    \[Find \frac{ dx }{ dy } for the following function. Y = sinx + 5e ^{0.4x}\]

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

    ok

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

    u allowed everyone to escape from this question hehehehe

  15. lovesit2x
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    lol i know, i wish i could escape it too

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

    dx/dy = 1/(dy/dx)

  17. lovesit2x
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    @jim_thompson5910 rescue me please

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

    ok i will solve it all it is implicit differentiation but in terms of x

  19. mathsmind
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    so when u diff sin(x) it will be cos(x)dx/dy

  20. mathsmind
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    and y will become 1 when u differentiate it

  21. lovesit2x
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    ok

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

    Just find dy/dx and take the reciprocal.

  23. mathsmind
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    nope don't do that

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

    they are not the same

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

    Look, dx/dy = 1/(dy/dx)

  26. mathsmind
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    no it does not work like that

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

    I hope you're kidding. I'm not manipulating fractions

  28. mathsmind
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    look multiply both sides

  29. mathsmind
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    u r missing the chain rule this is calculus not algebra

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

    http://math.stackexchange.com/questions/292590/is-dx-dy-1-dy-dx-in-calculus

  31. mathsmind
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    the case where u use a reciprocal is by using the chain rule and cancelling each term out

  32. Azteck
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Can't you implicit differentiate in this situation?

  33. Azteck
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    implicitly*

  34. mathsmind
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    yes that is different from ur fomula

  35. lovesit2x
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    im even more confused...

  36. mathsmind
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    he wants u to use L rule

  37. mathsmind
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    which is similar to what i said about the chain rule

  38. mathsmind
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Lebenz derived a formula from the chain rule

  39. Azteck
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    \[\large y=\sin x+5e^{0.4x}\] \[\large 1=(\cos x +2e^{0.4x})\frac{dx}{dy}\]

  40. mathsmind
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    nope i told u don't do that, unless if u want to apply Lebenz rule u need to take the inverse of the function then take the reciprocal ...

  41. mathsmind
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    because calculus is about functions and expansions

  42. mathsmind
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    read that carefully If the derivative of y = f(x) is dy/dx, then the derivative of the inverse function which expresses x in terms of y is given by the formula

  43. mathsmind
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    in other words ur Lebenz works if x= sin(y)+5e^y

  44. mathsmind
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    so u can take the inverse of the function then apply the rule ok

  45. mathsmind
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    i told u they are not the same but thanks anyway for bribing the topic up

  46. mathsmind
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    so take the inverse of the function then use the rule

  47. mathsmind
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    or solve it implicitly as i started

  48. mathsmind
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    if the case was simple like this then implicit differentiation would have never exist

  49. mathsmind
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    \[y = \sin(x) + e^{0.4x} \longrightarrow 1=\frac{dx}{dy}\cos(x)+2\frac{dx}{dy}e^{0.4x}\]

  50. mathsmind
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    the method u use is solving this in an implicit way

  51. mathsmind
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    take dx/dy as a common factor

  52. mathsmind
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    well @Xavier ur method also works congratulation!

  53. mathsmind
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    so both methods work fine, actually u made me come with a new theory in math, or a different proof for Leben'z formula. although maths is not my major, but i will write a new paper on this and publish it

  54. mathsmind
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    works*

  55. mathsmind
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    not just that i will change my proof for Kepler's laws of motion ...

  56. 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