2-2(coszcos2+sin2sinz)=2-2cos(z-2)= 2(1-cos(z-2))=
2(cos0-cos(z-2))=4sin^2(z/2-1)" alt="cos^2z-2coszcos2+cos^22+sin^22-2sin2sinz+sin^2z=
2-2(coszcos2+sin2sinz)=2-2cos(z-2)= 2(1-cos(z-2))=
2(cos0-cos(z-2))=4sin^2(z/2-1)" align="absmiddle" class="latex-formula">
по-моему так,проверьте