COMEDK2021MathematicsVector Algebra

If | a |=8,| b |=3 and | a b |=12 , then find the angle between a and b .

Options

A3
B6
C4
DNone of these

Correct answer

B. 6

Step-by-step solution

The magnitude of the cross product of two vectors a and b is given by the formula | a b | = | a | | b | , where is the angle between the vectors. Given | a | = 8 , | b | = 3 , and | a b | = 12 . Substituting these values into the formula: 12 = 8 3 12 = 24 = 12 24 = 1 2 Since = 1 2 , the possible values for are 6 or 5 6 . Comparing with the given options, 6 is present. Answer: 6

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