A community for students.

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

anonymous

  • one year ago

i need some help

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

    1 Attachment
  2. IrishBoy123
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    |dw:1441715548469:dw|

  3. IrishBoy123
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    have you got your equation for \(f^{-1}(x)\) yet??

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

    idk how to do anything with it my teacher never taught me how

  5. IrishBoy123
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    first, we'll re-write your equation as y = 2x - 6, so this takes in x values and returns y values now switch that around so that it says x = ... ie give me an equation that takes in y values and returns x values [you'll see what the point of this is when we're done]

  6. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    so takes in is the 2x-6 part and puts out is y=

  7. IrishBoy123
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    yes now switch it around so it says x = ....

  8. IrishBoy123
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    example y = 2x +1 x = y/2 - 1/2

  9. IrishBoy123
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    example y = 9x - 3 x = (1/9) (y+3)

  10. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    y-1/2=x

  11. IrishBoy123
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    example i start with y = 2x +1 i switch around to get x = y/2 - 1/2 example i start with y = 9x - 3 i switch around to get x = (1/9) (y+3) you are starting with y = 2x - 6 can you switch it around in same way?

  12. IrishBoy123
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    you can do it!

  13. IrishBoy123
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    i can do the first example is steps, if that helps??!!

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

    x=y/2-2/1

  15. IrishBoy123
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    ??

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

    idk im lost

  17. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    thats what i thought

  18. IrishBoy123
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    x=y/2-2/1 for you question?!?!?

  19. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    yes

  20. IrishBoy123
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    i'll try this 1st example \(y = 2x +1\) add -1 to each side \(y-1 = 2x +1-1\) so \(y-1 = 2x\) divide each side by 2 \(y/2-1/2 = 2x/2\) so \(y/2-1/2 = x\) just switch left hand and right hand sides around \(x = y/2-1/2\) and that is done

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

    and thats what u want me to find for my prob

  22. IrishBoy123
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    2nd example \(y = 9x - 3\) add 3 to each side \(y +3= 9x - 3+3\) so \(y +3= 9x \) divide each side by 9 \((1/9)(y +3)= 9x/9\) so \((1/9)(y +3)= x\) switch around \(x=(1/9)(y +3)\)

  23. IrishBoy123
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    yes if you truly have not been shown how to do this algebra, then you should really not be trying to do inverse functions...

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

    i must have missed that class but yeah

  25. IrishBoy123
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    well copy what i did and see how you go.

  26. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    x=(y/2)+(2/6)

  27. IrishBoy123
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    very good we can simplify a little, ie the 2/6, right?

  28. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    yes 3

  29. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    what happens now

  30. IrishBoy123
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    i'll do this bit as it's just notation, important notation but you havealready done the hard bit you recall we took your function \( f(x) = 2x - 6\) and re-wrote as \( y = 2x - 6\) so we could manipulate it a bit easier well we now take your solution for the inverse ie \( x=y/2+3\) and we re-write it as \(f^{-1}(x) =x/2 + 3 \) so or example \(f(3) = 0\), and hey presto \(f^{-1}(0) = 3\)!!! so you now take \(f^{-1}(x) =x/2 + 3 \) and answer the question

  31. IrishBoy123
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    they want \(f^{-1}(2)\)

  32. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    alright i followed and understood upto f(3)=0 and then i got lost

  33. IrishBoy123
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    no worries function \(f(x) = 2x - 6 = 0 \implies f(3) = 2(3) - 6 = 0\) inverse function \(f^{-1}(x) = x/2 + 3 \implies f^{-1}(0) = 0/2 + 3 = 3\)!! so we have function f and its inverse \(f^{-1}\). they reverse each other plugging into \(f^{-1}(x) = x/2 + 3\) for x = 2 \(f^{-1}(2) = (2)/2 + 3\)

  34. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    okay i think i get it

  35. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    so doo i solve f−1(2)=(2)/2+3

  36. IrishBoy123
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    yes

  37. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    f=1/2

  38. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    no thats wrong

  39. IrishBoy123
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    yes, go again

  40. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    5

  41. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    -5

  42. IrishBoy123
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    \[f^{-1}(2) = \frac{(2)}{2} + 3\]

  43. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    im lost a little

  44. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    what do i do with f^-1(2)

  45. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    so i just solve the answer part

  46. IrishBoy123
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    |dw:1441720473828:dw|

  47. IrishBoy123
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    yes just solve

  48. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    f−1(2)=4

  49. IrishBoy123
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    indeed

  50. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    thats my answer

  51. IrishBoy123
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    yes

  52. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    okay

  53. 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.