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I don’t understand what they did here... (C3 functions) watch

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    Could you please have a look at part c?

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    Why did they make f(x) = x??
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    Because f-1(x) is a reflection of f(x) in the line y = x
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    For functions of one variable the graph of an inverse function of a function is the graph of y=f(x) reflected in the line y=x and so if the curves touch at any points then they must touch on the line y=x and so f(x)=x and also f^(-1)(x)=x.
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    (Original post by B_9710)
    For functions of one variable the graph of an inverse function of a function is the graph of y=f(x) reflected in the line y=x and so if the curves touch at any points then they must touch on the line y=x and so f(x)=x and also f^(-1)(x)=x.
    Ah I understand now. Thank you for explaining!
 
 
 

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