Prove or disprove that T:[0,2π] -> [0,2π] given by Tx = sin(2014x) is a contraction

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i know that if we assume $T:[a,b] \to [a,b] $ and if $|T'(x)| ≤ α \space \forall \space a≤x≤b$ then T is a contraction .

but unsure of how to apply that to this question

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I think that you should add $\alpha < 1$ in your statement. So, you just have to show that there exists at least one $x\in[0, 2\pi]$ such that this inqequality doesn't hold. Do you have any ideas? Just take the derivative of the $\sin(2014x)$.

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I just did |T'(X)| = |2014 cos(2014x)| < sup (2014 cos(2014x)) and it was not smaller than 1 so T is not a contraction is that right?