- $ F\\\left( x \\\right) = - \\\cos 2x + {x^2} + C$
- $ F\\\left( x \\\right) = - \\\frac{{\\\cos 2x}}{2} + {x^2} + C$
- $ F\\\left( x \\\right) = \\\frac{{\\\cos 2x}}{2} + {x^2} + C$
- $ F\\\left( x \\\right) = \\\cos 2x + 2 + C$