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Let a → , b → , c → be three non-coplanar vectors such that a → × b → = 4 c → , b → × c → = 9 a → and c → × a → = α b → , α > 0 If a → + b → + c → = 36 , then α is equal to _______.

Correct answer

0

Step-by-step solution

Taking cross product of c → both side we get, a → × b → = 4 c → ⇒ a → × b → × c → = 0 ⇒ a → · c → . b → - b → · c → . a → = 0 ⇒ a → · c → . b → = b → · c → . a → Since vectors are non-coplanar so, ⇒ a → · c → = b → · c → = 0   . . . . . . 1 Similarly for b → × c → = 9 a → ⇒ a &#

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