1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Composition of Functions

  1. Mar 22, 2012 #1
    1. The problem statement, all variables and given/known data

    Define Function f: [0,1]x[0,2∏)→ℝ2 by

    f(r,θ)=

    (r(2+cos5θ)cosθ)
    (r(2+cos5θ)sinθ)

    Let g: [0,2∏)→[0,1]x[0,2∏) be defined by

    g(t)=

    (1)
    (t)

    Compute the function δ=f°g, what are the domain and codomain of δ?

    2. Relevant equations



    3. The attempt at a solution

    Replacing r with 1 and θ with t gives

    (2+cos5t)cost
    (2+cos5t)sint

    but this doesn't seem right
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     
    Last edited: Mar 22, 2012
  2. jcsd
  3. Mar 22, 2012 #2
    First, did you mean [itex]f(r,θ)=(r(2+cos5θ)cosθ,r(2+cos5θ)sinθ)[/itex] and [itex]g(t)=(1,t)[/itex]?

    Look at picture (attachment), and mark the function and you will see

    P.S. It seems well.
     

    Attached Files:

  4. Mar 22, 2012 #3
    yes, thats what I mean.

    thanks for the help

    I don't really understand the picture, but would the domain be the possible input of g, and the codomain the possible outputs of f?

    ie domain of [0,2∏) and codomain of ℝ2 ?
     
    Last edited: Mar 22, 2012
  5. Mar 22, 2012 #4
    ahh I get your picture now, I think I am right with the domain and codomain?
     
  6. Mar 22, 2012 #5
    Yes you are.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Composition of Functions
  1. Function Composition (Replies: 2)

  2. Function composition (Replies: 7)

  3. Function composition (Replies: 5)

  4. Functions composition (Replies: 2)

Loading...