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Question
If `bar c = 3bara- 2bar b ` Prove that `[bar a bar b barc]=0`
Solution
Given `barc=3bara-2barb`
Prove that `[bar a bar b barc]=0`
`barb xxbarb = 0` If in a scalar triple product, two vectors are equal, then the secalar triple product is zero.
`L.H.S=[bara barb barc]`
`=bara (barbxxbarc)`
`=bara(barbxx(3bara-2barb))`
`=bara(3baraxxbarb-2barbxxbarb)`
`=bara(3baraxxbarb-0)`
`=2baraxxbaraxxbarb`
`=2xx0xxbarb`
`=0`
Hence Proved
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