iran-konkur 2022 Q122

iran-konkur · Other · konkur-riazi_1401_specialized 4 marks Differentiation from First Principles
122-- If $f(x)=(x-4)\sqrt[4]{x+3}$, then $\displaystyle\lim_{h\to 0}\dfrac{f^{2}(\Delta-h)-3f(\Delta-h)+2}{h(\Delta-h)}$ is which of the following?
(1) $\dfrac{13}{30}$ (2) $-\dfrac{5}{12}$ (3) $\dfrac{5}{6}$ (4) $-\dfrac{13}{15}$
\textbf{122--} If $f(x)=(x-4)\sqrt[4]{x+3}$, then $\displaystyle\lim_{h\to 0}\dfrac{f^{2}(\Delta-h)-3f(\Delta-h)+2}{h(\Delta-h)}$ is which of the following?

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(1) $\dfrac{13}{30}$ \hfill (2) $-\dfrac{5}{12}$ \hfill (3) $\dfrac{5}{6}$ \hfill (4) $-\dfrac{13}{15}$

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