common.or
auth.dont_have_account auth.register
ab+bc+ca=0 হলে 1a2-bc + 1b2-ac+ 1c2-ab এর মান কত?
Given that, ab+bc+ca=0
∴ab+bc=-ca ∴ca=-(ab+bc) =ab+ca=-bc ∴=bc=-(ab+ca) =bc+ca=-ab ∴=ab=-(bc+ca) Again given that, 1a2-bc+1b2-ac+1c2-ab =1a2+ab+ca+1b2+ab+bc+1c2+bc+ca=1a(a+b+c)+1b(b+a+c)+1c(c+b+a) =1a(a+b+c)+1b(a+b+c)+1c(a+b+c)=1a(a+b+c)×(1a+1b+1c)=1a+b+c×(bc+ca+ab)abc =ab+bc+caabc(a+b+c)=0abc(a+b+c)=0
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