Question

Va rog ,raspundeti.........

Answer 1

|-2-4-6-..-2n|=2+4+6+..+2n= 2(1+2+..+n)=n(n+1)  *************
|-n|=n
sub radical avem asadar n(n+1)-n=n²+n-n=n²
atunci
√n²=|n|=n(ptca n>0)∈N*⊂N
as sofisticated as that!!


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mai greusa te [prinzi cand vezi  ditamai  cârna...ăăăăsta , ditamai suma algebrica
dar poate cu un exemplu concret vei intelege mai rapid
|-2-4-6|= |+2+4+6|=2+4+6
pt ca |x|=|-x| si 2+4+6=-(-2-4-6)