Mathematics · 2021
JEE Main · 31 August 2021, Shift 1 · Q83
If ' R ' is the least value of ' a ' such that the function f(x)=x^2+ a x+1 is increasing on [1,2] and ' S ' is the greatest value of ' a ' such that…
If ' R ' is the least value of ' a ' such that the function $\displaystyle f(x)=x^2+\mathrm{a} x+1$ is increasing on $\displaystyle [1,2]$ and ' $\displaystyle S$ ' is the greatest value of ' $\displaystyle a$ ' such that the function $\displaystyle f(x)=x^2+a x+1$ is decreasing on [$\displaystyle 1$, $\displaystyle 2$], then the value of $\displaystyle |\mathrm{R}-\mathrm{S}|$ is \_\_\_\_.
Official answer
2
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