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JEE Main202225 Jun 2022Morning ShiftMathematicsVector AlgebraActual

Let θ be the angle between the vectors a → and b → , where a → = 4 , b → = 3 and θ ∈ π 4 , π 3 . Then a → - b → × a → + b → 2 + 4 a → · b → 2 is equal to ______

Correct answer

0

Step-by-step solution

a → - b → × a → + b → 2 + 4 a → · b → 2 = a → × a → + a → × b → − b → × a → − b → × b → 2 + 4 a → ⋅ b → 2 = 4 a → × b → 2 + a → · b → 2 = 4 a → 2 b → 2 = 4 × 9 × 16 = 576

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