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Prove that the function f given by f(x)=...

Prove that the function `f` given by `f(x)=x-[x]` us ubcreasubg ub `(0,1)dot`

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Here, `f(x) = x-[x]`
We know, `x = [x] +{x}`, where `[x]` is the greatest integer function of `x` and `{x}` is the fraction of `x`.
`:. x - [x] = {x}`.
`:. f(x) = {x}`
Let `x_1 = 0.23` and `x_2 = 0.25`
Then, `f(x_2) gt f(x_1)`
It means, if `x_2 gt x_1` , then, `f(x_2) gt f(x_1)` for `x in (0,1).`
Therefore, `f(x)` is an increasing function in `(0,1)`.
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