标准形式:f(x)=Asin(wx+π/3)T=2π/w=4π(2)定义域为R,sin(1/2x+π/3)值域为【-1,1】f(x)max=3,此时1/2x+π/3=π/2+2kπ即x=π/3+2kπf(x)min=-3,此时1/2x+π/3=-π/2+2kπ即x=-5/3π+2kπ(3)x在【-2π,2π】上,1/2x+π/3属于【-2/3π,4/3π】单调区间,[-2/3π,-1/2π]和[1/2π,4/3π]单调减区间,(-1/2π,1/2π)单调增区间