5sin^2x-3,5sinxcosx+2cos^2x-3sin^2x-3cos^2x=02sin^2x-cos^2x-3,5sinxcosx=02tg^x-3,5tgx-1=0tgx=-1/4tgx=2x=arctg2+Пkx=-arctg(1/4)+Пk.