sinx与y=cosx与x=-4/π与x=-4/π构成的区域面积
问题描述：
sinx与y=cosx与x=-4/π与x=-4/π构成的区域面积
答
这其实就是求定积分-π/4≤x≤π/4时,cosx≥sinx∫(-π/4→π/4)(cosx-sinx)dx=[sinx+cosx]|(-π/4→π/4)=[sin(π/4)+cos(π/4)]-[sin(-π/4)+cos(-π/4)]=sin(π/4)-sin(-π/4)=√2/2-(-√2/2)=√2...