$$\frac{\partial}{\partial x} \left( \operatorname{acos}{\left(2 t \right)}, \ x\right)$$
2
d
---((acos(2*t), x))
2
dx
$$\frac{\partial^{2}}{\partial x^{2}} \left( \operatorname{acos}{\left(2 t \right)}, \ x\right)$$
3
d
---((acos(2*t), x))
3
dx
$$\frac{\partial^{3}}{\partial x^{3}} \left( \operatorname{acos}{\left(2 t \right)}, \ x\right)$$