Mathematics · 2020
JEE Main · 7 January 2020, Shift 2 · Q60
Let f(x) be a polynomial of degree 5 such that x= ± 1 are its critical points. If lim_x → 0(2+(f(x))/x^3)=4, then which one of the following is not…
Let $\displaystyle f(x)$ be a polynomial of degree $\displaystyle 5$ such that $\displaystyle x= \pm 1$ are its critical points. If $\displaystyle \lim _{x \rightarrow 0}\left(2+\frac{f(x)}{x^3}\right)=4$, then which one of the following is not true ?
Official answer
(4)
$\displaystyle x=1$ is a point of minima and $\displaystyle x=-1$ is a point of maxima of $\displaystyle f$.
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