Sin^3-1 over 4 sin/-90 degree to 90 degree/Curve behavior/Exercise

Discuss the behavior of the function

$f\colon [-{\frac {\pi }{2}},{\frac {\pi }{2}}]\longrightarrow \mathbb {R} ,x\longmapsto f(x)=\sin ^{3}x-{\frac {1}{4}}\sin x,$

concerning zeros, growth behavior, (local) extrema. Sketch the graph of the function.

Create a solution