解：∫arccosxdx =xarccosx-∫xd(arccosx) =xarccosx+∫xdx/√(1-x²) =xarccosx+(1/2)∫d(1-x²)/√(1-x²) =xarccosx+(1/2)∫[(1-x²)^(-1/2)]d(1-x²) =xarccosx+√(1-x²)+C 望采纳！
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