How to proof the derivative is continuous

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Q) Consider a function $f:(0,1) \to \mathbb{R}$, continuous annd differentiable. $(\alpha_n)^\infty_1$ be a sequence of roots of $f$ which converges to $\alpha \in (0,1)$. Prove that $f'(\alpha)=0$.

Here I am using Rolle's Theorem get a sequence $(c_n)_1^\infty$ such that $f'(c_n)=0$ and $Lt \, c_n=\alpha$. But after this I am not being able to prove that $f'(x)$ is continuous so that I can use the sequential criteria.