About norm and inverse operator $Af(x)=\int\limits_{0}^{x}f(t)dt$

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Problem :

Let $E=\left(\mathcal{C}[0,1],\|.\|_{\infty}\right)$

Defined operator $A$ :

$$A ~~:E\to~~E$$ $$Af(x)=\displaystyle\int\limits_{0}^{x}f(t)dt$$

  1. Prove that $\|A\|=1$

Then $A^{-1}$ existed , is bounded??


My attempts:

I was find $\|A\|\leq 1$

For $f≡1$ then $\|f\|_{\infty}=1$

But I can't get $\|Af\|_{\infty}=1$

The second question I need to prove $A$ are invective so ,

$Af(x)=0\implies \displaystyle\int\limits_{0}^{x}f(t)dt=0$

$\implies f(t)=0 $

by derivative both side is this correct??

And what about bounded of $A^{-1}$