分母等价无穷小替换为x^3,然后洛必达法则,再分子有理化即可,结果为-1/6或者分母等价替换为 (arcsin x)^3,然后令arcsin x=t,则 t 趋于0,x=sint,再洛必达法则即可
lim(x→0)(x-arcsinx)/(xsinxarctanx) = lim(x→0)(-1/6 x^3)/x^3 (等价无穷小代换) = -1/6答题不易,请及时采纳,谢谢!
原式 = lim(x-arcsinx)/x^3 (0/0)= lim(1-1/√(1-x^2)/(3x^2)= lim[√(1-x^2)-1]/[3x^2√(1-x^2)]= lim[(1-x^2)-1]/{3x^2[√(1-x^2)+1]}= -1/6