Let
 $f\left(\mathrm{x}\right)=({\mathrm{x}}^2-3\mathrm{x}+2)\left|({\mathrm{x}}^3-6{\mathrm{x}}^2+11\mathrm{x}-6)\right|+\left|\sin (\mathrm{x}+\frac{\mathrm{\pi }}{4})\right|$

number of points at which the function f (x) is non-differentiable in $[0,2\mathrm{\pi }]$ is