KCET2023MathematicsVector Algebra

If a +2 b +3 c =0 and ( a b )+( b c )+( c a )= ( b c ) , then the value of is equal to

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Correct answer

C. 6

Step-by-step solution

Given, a +2 b +3 c =0 aligned & (a+2 b+3 c) c=0 c a=2(b c) & (a+2 b+3 c) b=0 & a b=3(b c) aligned So, aligned & (b c)+(c a)+(a b)= (b c) & (b c)+2(b c)+3(b c)= (b c) & 6(b+c)= (b c) aligned On comparing with coefficient of ( b c ) , we get =6

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