解答过程如下:∫[-1,3][1/(x²+4x+5)]dx=∫[-1,3]{1/[(x+2)²+1]}dx=arctan(x+2)|[-1,3]=arctan3-arctan(-1)=3-(-π/4)=3+π/4我写过一道类似的,但是上限不同的,也给你附上:∫[-1,-3][1/(x²+4x+5)]dx=∫[-1,-3]{1/[(x+2)²+1]}dx=arctan(x+2)|[-1,-3]=arctan(1)-arctan(-1)=π/4-(-π/4)=π/2