Răspuns :
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(n+1)/(2n+1)=4/7
=>7(n+1)=4(2n+1)
7n+7=8n+4
8n-7n-7+4=0
n-3=0
n=3 deci C)
(n+1)/(2n+1)=4/7
=>7(n+1)=4(2n+1)
7n+7=8n+4
8n-7n-7+4=0
n-3=0
n=3 deci C)
n+1/2n+1=4/7
(n+1)*7=(2n+1)*4
7n+7=8n+4
8n-7n=7-4
n=3
Raspunsul este c)3.
(n+1)*7=(2n+1)*4
7n+7=8n+4
8n-7n=7-4
n=3
Raspunsul este c)3.