Question 703483
Here are the graphs of {{{y=sin(x)}}} and {{{y=-1)))from {{{-pi/2}}} to {{{9*pi/2=about 14.3}}}.
{{{graph(300,100,-pi/2, 9*pi/2,-1.5,1.5,sin(x),-1)}}}
You can see that {{{y=sin(x)=-1}}} twice in that interval.
It happens for {{{x=highlight(3pi/2)}}} ({{{270^o}}} or {{{3/4}}} of a counterclockwise turn).
It happens again {{{2pi}}} (a full turn) later,
at {{{x=2pi+3pi/2=highlight(7pi/2)}}}.