If `veca,vecb and vecc` are non coplnar and non zero vectors and `vecr` is any vector in space then`[vecc vecr vecb]veca+pveca vecr vecc] vecb+[vecb v

Monjur Alahi

If `veca,vecb and vecc` are non coplnar and non zero vectors and `vecr` is any vector in space then`[vecc vecr vecb]veca+pveca vecr vecc] vecb+[vecb vecr veca]c=` (A) `[veca vecb vecc]` (B) `[veca vecb vecc]vecr` (C) `vecr/([veca vecb vecc])` (D) `vecr.(veca+vecb+vecc)`


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Salim Ahmed Kawsar

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`Let" " vecr=x_(1)veca+x_(2)vecb+x_(3)veccRightarrow vecr.(vecbxxvecc)=x_(1)veca.(vecbxxvecc)or x_(1)=([vecr vecb vecc])/([veca vecb vecc])`.
`Also, " " vecr.(veccxxveca)=x_(2)vecb.(veccxxveca)orx_(2)=([vecrveccveca])/([vecavecbvecc])`
`and vecr.(vecaxxvecb)=x_(3)vecc. (vecaxxvecb)or x_(3)=([vecr vecavecb])/([veca vecbvecc])`
`Rightarrow vecr=([vecrvecb vecc])/([vecavecbvecc])veca+([vecrveccveca])/([vecavecbvecc])vecb+([vecrvecavecb])/([vecavecb vecc])vecc`
`or [vecbveccvecr]veca+[veccvecavecr]vecb+[vecavecbvecr]vecr=[vecavecbvecc]vecr`

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