What are the points of inflection of $f(x)=xcosx$ on the interval $x in [0,2pi]$ ?

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Answer 1 · 2018-06-21T07:19:44

$f'(x)=cos(x)-xsin(x)$
$f"(x)=-2sin(x)-xcos(x)$
set $f"(x)=0$ for points of inflection, x=0, 2.29

On your calculator let equation 1 be $y=2sin(x)$
let equation 2 be $y=-xcos(x)$
Find the points of intersection in $[0, 2pi]$

What are the points of inflection of f(x)=xcosx f(x)=xcosx on the interval x in [0,2pi]x in [0,2pi]?