[tex]f(x) = 5 {x}^{3} - 6 {x}^{2} + 18 \\ f'(x) = 5 \times 3 {x}^{3 - 1} - 6 \times 2 {x}^{2 - 1} = \\ 15 {x}^{2} - 12x = 15x(x - \frac{12}{15} ) = \\ 15x(x - 0.8) \\ f'(x) = 0 \\ 15x(x - 0.8) = 0 \\ x _{1} = 0\\ x_{2} = 0.8 \\ + + + [0] - - - [0.8] + + + \\ x _{max} =0 \\ x_{min} = 0.8[/tex]