If a=2i+j+3k and b=3i+5j-2k ,then find ∣a×b∣ - Mathematics

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If `veca=2hati+hatj+3hatk and vecb=3hati+5hatj-2hatk` ,then find ` |veca xx vecb|`

 
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Solution

 
 

Given that `veca=2hati+hatj+3hatk and vecb=3hati+5hatj-2hatk`

we need to find `|veca xx vecb|`

`veca xx vecb=|[i,j,k],[2,1,3],[3,5,-2]|`

`=hati(-2-15)-hatj(-4-9)+hatk(10-3)`

`=-17hati+13hatj+7hatk`

Hence, `|veca xx vecb| =sqrt(17^2+13^3+7^2)`

`=>|veca xx vecb|=sqrt(507)`

 
 
Concept: Vectors Examples and Solutions
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2014-2015 (March) Panchkula Set 1

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