JEE MATHEMATICS MCQ: DOT PRODUCT OF VECTORS

1 Easy

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Analyzing +4 | -1

Let three vectors

a

b

and

c

be such that

a \times b = c,\,\,b \times c = a

and

\left| a \right| = 2

. Then, which one of the following is not true?

View answer and explanation

Correct option: D

{\left| {3a + b - 2c} \right|^2} = 51

Option D (

{\left| {3a + b - 2c} \right|^2} = 51

) is not true because by using the given conditions and vector properties, the correct value of the expression is 53, not 51.

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