y=(sinx)/x 图像怎么作?
问题描述：
y=(sinx)/x 图像怎么作?
答
f(x)=2cosxsin(x+π/3)-根号3 (sinx)2+sinxcosx=2cosx(sinxcosπ/3+cosxsinπ/3)-根号3 (sinx)2+sinxcosx=根号3(cosx^2-sinx^2)+sin2x=根号3cos2x+sin2x=2cos(2x-π/6)最小正周期为π,值域=【-2,2】,递增区间=（kπ-...