JEE MAIN - Mathematics (2024 - 27th January Morning Shift - No. 23)

Let $f(x)=x^3+x^2 f^{\prime}(1)+x f^{\prime \prime}(2)+f^{\prime \prime \prime}(3), x \in \mathbf{R}$. Then $f^{\prime}(10)$ is equal to ____________.
Answer
202

Explanation

$$\begin{aligned} & f(x)=x^3+x^2 \cdot f^{\prime}(1)+x \cdot f^{\prime \prime}(2)+f^{\prime \prime \prime}(3) \\ & f^{\prime}(x)=3 x^2+2 x f^{\prime}(1)+f^{\prime \prime}(2) \\ & f^{\prime \prime}(x)=6 x+2 f^{\prime}(1) \\ & f^{\prime \prime \prime}(x)=6 \\ & f^{\prime}(1)=-5, f^{\prime \prime}(2)=2, f^{\prime \prime \prime}(3)=6 \\ & f(x)=x^3+x^2 \cdot(-5)+x \cdot(2)+6 \\ & f^{\prime}(x)=3 x^2-10 x+2 \\ & f^{\prime}(10)=300-100+2=202 \end{aligned}$$

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