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    Dear Math helpers,

    I need a clarification.
    WHat does it mean when you are asked:
    find the elements of the domain that get mapped to themselves by the function


    i partly understand but i need someone to explain it better in order to fully understand it

    thank you
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    Let's pose f(x)=x^2-1.
    What the function does basically is it takes elements from the set of x and plugs them in f(x) to output/map as a value in another set.

    When you're asked to find elements of the domain that are mapped to themselves, you need to find values of x for which y=x.
    With f(x)=x^2-1, you'd then pose f(x)=x.
    x=x^2-1
    0=x^2-x-1
    x=-0.618, 1.618
    Hence there are points (-0.618, -0.618) and (1.618, 1.618) on f(x) such that y=x.
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    (Original post by bigmansouf)
    Dear Math helpers,

    Take a function f(x), for what x is f(x) = x? Solve that equation and you're done. i.e: you want to compute the fixed points of f, for a sufficiently crude definition of fixed point.
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    (Original post by Zacken)
    Take a function f(x), for what x is f(x) = x? Solve that equation and you're done. i.e: you want to compute the fixed points of f, for a sufficiently crude definition of fixed point.
    (Original post by MartyO)
    Let's pose f(x)=x^2-1.
    What the function does basically is it takes elements from the set of x and plugs them in f(x) to output/map as a value in another set.

    When you're asked to find elements of the domain that are mapped to themselves, you need to find values of x for which y=x.
    With f(x)=x^2-1, you'd then pose f(x)=x.
    x=x^2-1
    0=x^2-x-1
    x=-0.618, 1.618
    Hence there are points (-0.618, -0.618) and (1.618, 1.618) on f(x) such that y=x.
    thank you to you both more q on the way thanks
 
 
 
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