MathDB
increasing/decreasing function

Source: LIMIT 2019 CBS1 P8

April 28, 2021
function

Problem Statement

If f(x)=cos(x)1+x22f(x)=\cos(x)-1+\frac{x^2}2, then <spanclass=latexbold>(A)</span> f(x) is an increasing function on the real line<span class='latex-bold'>(A)</span>~f(x)\text{ is an increasing function on the real line} <spanclass=latexbold>(B)</span> f(x) is a decreasing function on the real line<span class='latex-bold'>(B)</span>~f(x)\text{ is a decreasing function on the real line} <spanclass=latexbold>(C)</span> f(x) is increasing on <x0 and decreasing on 0x<<span class='latex-bold'>(C)</span>~f(x)\text{ is increasing on }-\infty<x\le0\text{ and decreasing on }0\le x<\infty <spanclass=latexbold>(D)</span> f(x) is decreasing on <x0 and increasing on 0x<<span class='latex-bold'>(D)</span>~f(x)\text{ is decreasing on }-\infty<x\le0\text{ and increasing on }0\le x<\infty