a+b +c =9 , a2+b2+c2=29 হলে ab +bc + ca = কত?
a+b +c =9 , a2+b2+c2=29 হলে ab +bc + ca = কত? Correct Answer 26
2(ab + bc + ca) = (a + b + c)2 - (a2 + b2 + c2) = 92 - 29 = 52 = > ab + bc + ca = 52/2 = 26
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Feb 20, 2025