X^3⼀根号下(1+x^2)的原函数,求详细过程

X^3/根号下(1+x^2)的原函数,求详细过程
2025-01-21 05:58:25
推荐回答(1个)
回答1:

解: X^3/根号下(1+x^2)的原函数=∫[x^3/(√1+x^2)]dx
=1/2∫[x^2/(√1+x^2)]d(x^2)
=1/2∫[(x^2+1-1)/(√1+x^2)]d(x^2)
=1/2∫(√1+x^2)d(x^2+1)-1/2∫[1/(√1+x^2)](d(x^2+1)
=1/2[(2/3)(x^2+1)^(3/2)-2(√1+x^2)]
=(x^2-2)(√1+x^2)/3