lim[(x h)^3 - x^3]/h
=lim[3x^2? 3x * h^2 h^3]/h
=lim[3x^2 3x * h h^2]
=lim(3x^2) lim(3x h) lim (h)^2
=3x^2 lim(3x * 0) lim(0)^2
=3x^2
=lim(1 u^3)^(1/4)/(1 u)
=lim[(1 u^3)/(1 u)^4]^(1/4)
= lim[(1 u)(1-u u^2)/(1 u)^4]^(1/4)
=lim[(1-u u^2)/(1 u)^3]^(1/4)
=lim[(1-u u^2)/(1 3u 3u^2 u^3)]^(1/4)
= lím {[(1/u)3-(1/u)2 (1/u)]/[(1/u)3 3 *(1/u)
=lím [(0^3-0^2 0)/(0^3 3*0^2 3 * 0 1)]^(1/4)
=lim[0/1]^(1 /4)
=0