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प्रश्न
Find the magnitude of each of two vectors `veca` and `vecb` having the same magnitude such that the angle between them is 60° and their scalar product is `9/2`
उत्तर
Let the two vectors be `veca` and `vecb`
Since the vectors having same magnitude se,
`|veca| = |vecb|`
Scala product of the two vectors = `veca.vecb = |veca||vecb|cos theta`
`=> 9/2 = |veca||vecb| cos 60^@`
`=> 9/2 = |veca||vecb| xx 1/2`
`=> |veca||vecb| = 9` (From (1))
`=> |veca|^2 = 9`
`=> |veca| = |vecb| = 3`
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