Let's find the inflection points, we'll need to solve the equation for this
$$\frac{d^{2}}{d x^{2}} f{\left(x \right)} = 0$$
(the second derivative equals zero),
the roots of this equation will be the inflection points for the specified function graph:
$$\frac{d^{2}}{d x^{2}} f{\left(x \right)} = $$
the second derivative$$\left(\sin^{2}{\left(x \right)} - \cos{\left(x \right)}\right) e^{\cos{\left(x \right)}} = 0$$
Solve this equationThe roots of this equation
$$x_{1} = - 2 \operatorname{atan}{\left(\sqrt{-2 + \sqrt{5}} \right)}$$
$$x_{2} = 2 \operatorname{atan}{\left(\sqrt{-2 + \sqrt{5}} \right)}$$
Сonvexity and concavity intervals:Let’s find the intervals where the function is convex or concave, for this look at the behaviour of the function at the inflection points:
Concave at the intervals
$$\left(-\infty, - 2 \operatorname{atan}{\left(\sqrt{-2 + \sqrt{5}} \right)}\right] \cup \left[2 \operatorname{atan}{\left(\sqrt{-2 + \sqrt{5}} \right)}, \infty\right)$$
Convex at the intervals
$$\left[- 2 \operatorname{atan}{\left(\sqrt{-2 + \sqrt{5}} \right)}, 2 \operatorname{atan}{\left(\sqrt{-2 + \sqrt{5}} \right)}\right]$$