MHT CET202313 May 2023Evening ShiftMathematicsVector AlgebraActual
If the vectors p i + j + k , i +q j + k and i + j +r k ( p q r 1) are coplanar, then the value of pq r -( p + q + r ) is
Options
- A-2
- B2
- C0
- D-1
Correct answer
A. -2
Step-by-step solution
Since pi + j + k , i + q j + k and i + j + rk are coplanar, | array lll p & 1 & 1 1 & q & 1 1 & 1 & r array |=0 aligned & p(q r-1)-1(r-1)+1(1-q)=0 & p q r-p-q-r+2=0 & p q r-(p+q+r)=-2 aligned