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If |veca|=10,|vecb|=2andveca.vecb=12, th...

If `|veca|=10,|vecb|=2andveca.vecb=12`, then the value of `|vecaxxvecb|` is

A

5

B

10

C

14

D

16

Text Solution

Verified by Experts

The correct Answer is:
D
Here, `|veca|=10,=2andveca.vecb=12` [given]
`veca.vecb=|veca||vecb|costheta`
`12=10xx2costheta`
`impliescostheta=(12)/(20)=(3)/(5)`
`impliessintheta=sqrt(1-cos^(2)theta)=sqrt(1-(9)/(25)`
`sintheta=+-(4)/(5)`
`:.|vecaxxvecb|=|veca||vecb||sintheta|`
`=10xx2xx(4)/(5)`
=16
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