\ \sin x=1==>\ x=\frac{\pi}{2}+2\pi n, n\in Z\\
y(0)=\cos0+0-\frac{\pi}{3}=1-\frac{\pi}{3}=\frac{3-\pi}{3}<0;\\
y(\frac{\pi}{2})=\cos\frac{\pi}{2}+\frac{\pi}{2}-\frac{\pi}{3}=0+\pi(\frac{1}{2}-\frac{1}{3})=\\
=\pi(\frac{3-2}{2\cdot3})=\pi\frac{1}{6}=\frac{\pi}{6}>0;\\
y_{max}=\frac{\pi}{6}
" alt="y=\cos x+x-\frac{\pi}{3},\ x\in[0;\frac{\pi}{2}];\\
y'=-\sin x+1;\\
y'=0;\\
1-\sin x=0;==>\ \sin x=1==>\ x=\frac{\pi}{2}+2\pi n, n\in Z\\
y(0)=\cos0+0-\frac{\pi}{3}=1-\frac{\pi}{3}=\frac{3-\pi}{3}<0;\\
y(\frac{\pi}{2})=\cos\frac{\pi}{2}+\frac{\pi}{2}-\frac{\pi}{3}=0+\pi(\frac{1}{2}-\frac{1}{3})=\\
=\pi(\frac{3-2}{2\cdot3})=\pi\frac{1}{6}=\frac{\pi}{6}>0;\\
y_{max}=\frac{\pi}{6}
" align="absmiddle" class="latex-formula">