AP EAMCET202123 Aug 2021Evening ShiftMathematicsVector AlgebraActual
The figure formed by the four points ( i + j - k ),(2 i +3 j ),(5 j -2 k ) and ( k - j ) is
Options
- Atrapezium
- Brectangle
- Cparallelogram
- Dquadrilateral
Correct answer
D. quadrilateral
Step-by-step solution
Let O A = i + j - k aligned O B & =2 i +3 j O C & =5 j -2 k O D & = k - j aligned A B =O B-O A= i +2 j + k aligned | A B | & = 1^2+2^2+1^2 = 6 B C & = O C - O B =-2 i +2 j -2 k aligned aligned | B C | & = (-2)^2+2^2+(-2)^2 =2 3 C D & = O D - O C =-6 j +3 k aligned aligned | C D | & =3 5 D A & = O A - O D = i +2 j -2 k aligned | D A |=3 All the sides has different length and no two sides are equal and parallel. Hence, it forms only quadrilateral.