解:
∫(-π/2→π/2)[sinx/(1+x²)+cos²x]
dx
=∫(-π/2→π/2)[sinx/(1+x²)+(cos2x+1)/2]
dx
=∫(-π/2→π/2)sinx/(1+x²)dx+∫(-π/2→π/2)(cos2x+1)/2
dx
=0+2∫(0→π/2)(cos2x+1)/2
dx
=2[(sin2x)/4+x/2]
|(-π/2→π/2)
=2{[(sinπ)/4+π/4]-[(sin0)/4+0/2]}
=π/2
【注意被积函数sinx/(1+x²)是奇函数,(cos2x+1)/2是偶函数】