函数y=3sin(x+20°)+5cos(x-10°)的最大值是______

热心网友

y=3sin(x+20°)+5cos(x-10°)=3sinxcos20°+3cosxsin20°+5cosxcos10°+5sinxsin10°=sinx(3cos20°+5sin10°)+cosx(3sin20°+5cos10°)=√(9+25+30sin30°)*sin(x+w)=7sin(x+w)最大值是7