1. Example-1
1. Find AxB
`A=(3,1,1)`,`B=(-1,2,1)`
Solution:
Here `vec A=(3,1,1),vec B=(-1,2,1)`
`vec A xx vec B`
`=|[i,j,k],[A_1,A_2,A_3],[B_1,B_2,B_3]|`
`=|[i,j,k],[3,1,1],[-1,2,1]|`
`=i(1xx1-1xx2)-j(3xx1-1xx(-1))+k(3xx2-1xx(-1))`
`=i(1-2)-j(3+1)+k(6+1)`
`=-i-4j+7k`
`=(-1,-4,7)`
2. Find BxA
`A=(2,3,1)`,`B=(0,5,6)`
Solution:
Here `vec A=(2,3,1),vec B=(0,5,6),vec C=(2,3,1)`
`vec B xx vec A`
`=|[i,j,k],[B_1,B_2,B_3],[A_1,A_2,A_3]|`
`=|[i,j,k],[0,5,6],[2,3,1]|`
`=i(5xx1-6xx3)-j(0xx1-6xx2)+k(0xx3-5xx2)`
`=i(5-18)-j(0-12)+k(0-10)`
`=-13i+12j-10k`
`=(-13,12,-10)`
This material is intended as a summary. Use your textbook for detail explanation.
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