min{1/2,cosx}=1/2 -π/3≤x≤π/3=cosx -π/2≤x<π/3或π/3它是一个偶函数,从而xmin{1/2,cosx}是奇函数。故∫[x=-π/2,π/2](x+1)min{1/2,cosx}dx=∫[x=-π/2,π/2]min{1/2,cosx}dx=1/2*∫[x=-π/3,π/3]1dx+2∫[x=π/3,π/2]cosxdx=π/3+2sinx|[x=π/3,π/2]=π/3+2(sinπ/2-sinπ/3)=π/3+2-√3
2-根号3+pi/3
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