The following is the detailed process of definite integral calculation
Look at the picture
Finding definite integral (upper 3, lower 0) x ^ 2DX / (x ^ 2-3x + 3) ^ 2
Finding the value of definite integral ∫ (- 1,0) (3x ^ 4 + 3x ^ 2 + 1) / x ^ 2 + 1dx
The idea should be to change the molecule into several formulas with x ^ 2 + 1, and it doesn't matter if there are many constants. 1 / x ^ 2 + 1 is the derivative of arctanx. I hope you can work it out