Convergence of operator-exponential

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Let $T: [0,\infty) \rightarrow L(X)$ define a $C_0$ semigroup on a Banach space $X$, then I want to show that $A_h:=\frac{T(h)-id}{h}$ are such that $e^{tA_h}(f) \rightarrow T(t)(f)$ pointwise. Clearly, $A_h \in L(X),$ so that the exponential is defined, but I don't get the limit. Does anybody have an idea how this can be done?