1) 1+x=t³ t=∛(1+x) x->0 t->1
x=t³-1=(t-1)(t²+t+1)
x/((∛(1+x)-1) =(t-1)(t²+t+1)/(t-1)=t²+t+1
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=lim (t²+t+1) =3
t⇒1
ответ 3
2)
t^(15) =x; x⇒1 t⇒1
x^(1/5) =t³
x^(1/3)=t^5
(1-x^(1/3)) / (1-x^(1/5)) =(1-t^5) / (1-t³) = t² +(1-t²)/(1-t³)=
=t²+ (1-t²)/ ((1-t)² *(t²+t+1)) =t² +1/(t²+t+1)
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= lim (t²+1/(t²+t+1)=(1+1/3) =1 1/3
t⇒1
ответ 1 1/3