A community for students.

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

anonymous

  • one year ago

Let f(x) = 3x2 – x + 2 and g(x) = 5x2 – 1. Find f(g(x)).

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

    @johnweldon1993

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

    Will medal AND fan <3

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

    bec you have to substitute x for x you will get same equation so just substitute g(x) equation into f(x)

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

    I'm confused

  5. Astrophysics
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    \[f(g(x)) = 3(5x^2-1)-(5x^2-1)+2\] notice we take the function g(x) and plug it everywhere there is an x in f(x) which means f(g(x)).

  6. Astrophysics
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    \[f(g(x)) = 3(5x^2-1)^2-(5x^2-1)+2\] this is the proper one

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

    Ok. I see

  8. Astrophysics
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Now you may simplify it :)

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

    Can you wait until I finish so you can check my answer? :)

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

    15x^2-3-5x^2+7 yes?

  11. Astrophysics
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Mhm, not quite, notice it's \[3(5x^2-1) \huge ^{2}\]

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

    Ok. I don't understand

  13. Astrophysics
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    \[(5x^2-1)^2 \implies (5x^2-1)(5x^2-1)\]

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

    Ohh! Okay

  15. Astrophysics
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Yup :)

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

    25x^4-10x^2+1

  17. Astrophysics
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Awesome, now lets multiply it by 3 \[3(25x^4-10x^2+1)\]

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

    75x^4-30x^2+3

  19. Astrophysics
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    That's great :D, now we have \[75x^4-30x^2+3 -(5x^2-1)+2\]

  20. Astrophysics
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Now simplify it a bit more

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

    75x^4-30x^2-5x^2+3

  22. Astrophysics
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Good one more step though, look for like terms

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

    75x^4-35x^2+3

  24. Astrophysics
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Yup, nice work!!

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

    Is that it?

  26. Astrophysics
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Yup, we're done :)

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

    Can I ask one more please? :)

  28. Astrophysics
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    \[f(g(x)) = 75x^4-35x^2+3\]

  29. Astrophysics
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Unless you want solutions to it as well, but I doubt it, since it's gross...and sure :)

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

    Lol okay thanks :)

  31. Astrophysics
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    And we are solving for x? :)

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

    Solve the equation for the variable. Show each step of your solution process.

  33. Astrophysics
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Sounds fun, any idea how to start

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

    And yes :) You know, the usual

  35. Astrophysics
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    See if you can do anything with the 4

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

    subtract it from 5?

  37. Astrophysics
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Yup

  38. Astrophysics
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    |dw:1434493963942:dw| so far so good right

  39. Astrophysics
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Now do you know how to deal with the square root

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

    square both sides?

  41. Astrophysics
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Yes! And I'll show you why exactly we do that, so it makes sense...so when we have squareroot anything it means this \[\huge \sqrt{x} \implies x^{1/2}\] and notice if we square it we get 2/2 hence x^1 :), so squaring both sides would be the proper thing to do!

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

    Yay :)

  43. Astrophysics
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Alright so we should have what now?

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

    Add 3 to both sides?

  45. Astrophysics
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    |dw:1434494236543:dw|

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

    So, subtract 3 I meant

  47. Astrophysics
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Yes :), and our answer will be? :D

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

    x=-2

  49. Astrophysics
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Yes!! |dw:1434494432642:dw|

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

    HAHAHA :D Yesssss

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

    Ok last one, and I'm done. Pleaseeee

  52. Astrophysics
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Lol ok ok

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

    Given the expression 5a2b – 13ab + 7a3 – 4b, do the following as instructed below: Write the polynomial in descending order. Classify the polynomial by the number of terms. State the degree of the polynomial.

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

    Thank you friend!! *Huge internet hug*

  55. Astrophysics
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Ok lets do it step by step, descending order just means greatest to least (look at the a's). So go ahead and do that now :)

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

    Isn't it greatest to least?

  57. Astrophysics
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Yes, I made a mistake xD

  58. Astrophysics
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Tried to fix it before you saw haha, but nice catch!

  59. Astrophysics
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Good! Now lets state the terms, and figure out what kind it is!

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

    polynomial?

  61. Astrophysics
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Yes, but I think they might want you to say quadrinomial (meaning 4)

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

    oh okay :)

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

    what about the degree?

  64. Astrophysics
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    degree is the highest number of the variables, so we have to sum up the variables for the highest degree, can you figure out which one? :)

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

    3

  66. Astrophysics
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Yup, and that's it!

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

    :( Thank you so much for all your help! You were probably the nicest tutor on here I've met so far!!!

  68. Astrophysics
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Haha, thanks and your welcome :)

  69. 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.