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प्रश्न
Choose the correct alternative:
If `vec"a" = hat"i" + 2hat"j" + 2hat"k", |vec"b"|` = 5 and the angle between `vec"a"` and `vec"b"` is `pi/6`, then the area of the triangle formed by these two vectors as two sides, is
पर्याय
`7/4`
`15/4`
`3/4`
`17/4`
उत्तर
`15/4`
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