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If f: Rvec is defined by f(x) = 3x – 5 P...

If `f: Rvec` is defined by `f(x) = 3x – 5` Prove that `f` is a bijection. Also, find the inverse of `fdot`

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`{P}({x})=3 {x}-5`

Let `{y}=3 {x}-5 Rightarrow 3 {x}={y}+5`

`{x}=({y}+5) / 3`

Let `g(y)=frac{y+5}{3}`

Now `g circ f(x)=g[(f(x)]=g(3 x-5)`

also `f circ g(y)=frac{3 x-5+5}{3}=x[g(y)]=f[frac{y+5}{3}]`

Thus `g circ f=3(frac{y+5}{3})-5=y+5-5=y`

`f` and `g` are bijections and inverse to each other.

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