(1)y=4-3sin(x-π/3)
sinx的值域为[-1,1],所以,4-3sin(x-π/3) 值域为[1,7]
(2)y=cos^2x-sinx =1-2sin^2x-sinx=-2(sin^2x+1/2sinx+1/16)+9/8
=-2(sinx-1/4)^2+9/8
sinx的值域为[-1,1],(sinx-1/4)^2值域为[0,25/16]
cos^2x-sinx 值域为[-2,9/8]
(1)y=4-3sin(x-π/3)
sinx的值域为[-1,1],所以,4-3sin(x-π/3) 值域为[1,7]
(2)y=cos^2x-sinx =1-2sin^2x-sinx=-2(sin^2x+1/2sinx+1/16)+9/8
=-2(sinx-1/4)^2+9/8
sinx的值域为[-1,1],(sinx-1/4)^2值域为[0,25/16]
cos^2x-sinx 值域为[-2,9/8]