∫[x^3/(9+x^2)]dx答案是x^2/2-9/2*ln(x^2+9)+C

∫[x^3/(9+x^2)]dx答案是x^2/2-9/2*ln(x^2+9)+C ∫x^3/9+X^2 dx. ∫3+x/(9-x^2)dx ∫x^3/(9+x^2)dx ∫[xe^x/(1+x)^2]dx答案给的是e^x/(1+x) +c x-9/[(根号)x]+3 dx ∫ x+1/[(根号)x] dx ∫ [（3-x^2）]^2 dx ∫2^x*3^x/(9^x-4^x) dx答案有点出入感觉 ln|(3^x+2^x)/(3^x-2^x)|+C / 2(ln2-ln3) 求∫dx/x(9-x^2)^0.5的解,要过程问题是∫dx/x(9-x^2)^0.5答案是1/3ln((3-(9-x^2)^0.5)/x) 求不定积分(1-x^2)^3/2dx答案是x/根号(1-x^2) +c 不定积分dx/根号((x^2+1)^3) 答案是x/根号（1+x^2）+c 求∫[(ln(x+1)-lnx)/(x(x+1))]dx答案是(-1/2)(ln[(x+1)/x])^2+c 2x-1/ x^2-x+3 dx 不定积分 答案是ln(x^2-x+3 )+c f'(x^3)dx=x^3+c 则f(x)=?∫f'(x^3)dx=x^3+c 则f(x)=?答案是（9/5）x^(5/3)+c 已知∫xf(x)dx=arcsinx+C,求∫1/f(x)dx答案是-1/3(1-x^3)^2+C ∫[(x^2-x+6)/(x^3+3x)]dx ∫x/(4+9x^2)dx ∫dx/x(2x+3)^2 ∫(2^x+3^x)²dx