Question

If `f(x) = 2 sin x + sin 2x`, what are the points of inflection, concavity and critical points?

Answer 1

See the answers in the work below.

Explanation:

Credits:
Thanks to the following sources that helped us to remember the concepts of critical points, points of inflection, concavity and convexity and contributed to work that was not very difficult to understand.

https://www.math.hmc.edu/calculus/tutorials/secondderiv/

https://www.symbolab.com/solver/function-inflection-points-calculator

http://www.sangakoo.com/en/unit/concavity-and-convexity-inflection-points-of-a-function

In Portuguese:

https://www.math24.net/inflection-points/

In Portuguese: http://pt.wikihow.com/Determinar-as-Coordenadas-de-um-Ponto-de-Inflex%C3%A3o-de-uma-Fun%C3%A7%C3%A3o