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limx->1 din (x+1)la2 -4 / (x+3)la2 -16
help pls


Răspuns :

lim[(x+1)²-4]/[(x+3)²-16]=
x->1
=lim(x+1-2)(x+1+2)/(x+3-4)(x+3+4)=
x->1
=lim(x-1)(x+3)/(x-1)(x+7)=
x->1
=lim(x+3)/(x+7)=4/8=1/2
x->1
dac inlocui,ca pt functii continue, obtinem 0/0 nedeterminare


atunci descmpunem
lim cand   x->1 din[ (x+1-2)(x+1+2)]/[(x+3-4)(x+3+4)]
lim cand x->1 din [(x-1)(x+3)]/[(x-1)(x+7)]= simplificam cu x-1≠0=
lim cand x->1din (x+3)/(x+7)=4/8=1/2