Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
MHT CET202526 Apr 2025Morning ShiftMathematicsVector AlgebraActual

If a = x i + y j +4 z k , ~b = y i +x j +3 y k , c =- z i -2 z j -( +1) k x are the sides of the triangle ABC , where x, y , z are not all zero, such that a + b - c = 0 , then value of is

Options

  1. A0
  2. B1
  3. C2
  4. D3

Correct answer

A. 0

Step-by-step solution

Given vectors a = x i + y j + 4z k , b = y i + x j + 3y k , and c = -z i - 2z j - ( +1)x k with a + b - c = 0 , we substitute and group components. The i component yields x + y + z = 0 The j component gives x + y + 2z = 0 The k component results in ( +1)x + 3y + 4z = 0 This homogeneous system has nontrivial solutions only if the coefficient matrix determinant is zero: pmatrix & 1 & 1 1 & 1 & 2 +1 & 3 & 4 pmatrix = (4-6) - 1(4-2 -2) + 1(3- -1) = -2 - 2 + 2 + 2 - = - Setting - = 0 gives the solution = 0 . Final answe

Practice Vector Algebra on Quantrex Academy →

More from Vector Algebra

P is the circumcentre of A B C . If the position vectors of A, B, C and P are a , b , c , a + b + c 4 respectively, then the position vector of the orthocentre of this triangle is 2025If the position vectors of A, B, C, D are i +2 j +2 k , 2 i - j , i + j +3 k and 4 j +5 k respectively, then the quadrilateral ABCD is a 2025The set of all real values of c so that the angle between the vectors a = cx i -6 j +3 k and b =x i +2 j +2 cx k is an obtuse angle for all real x is 2025Let a =2 i + j +3 k , b =3 i +3 j + k and c = i -2 j +3 k be three vectors. If r is a vector such that r a = r b and r c =18 , then the magnitude of the orthogonal projection of 4 2025If u , v , w are non coplanar vectors and p, q are real numbers, then the equality [ array lll 3 u & p v & p w array ]- [ array lll p v & w & q u array ]- [ array lll 2 w & q v & q 2025Let i -2 j + k , i + j -2 k , 2 i - j - k and i + j + k be the position vectors of four points A , B , C and D respectively. If a point P divides AB in the ratio 2: 1 internally an 2025If a = i + j , b =2 j - k are two vectors such that r a = b a , r b = a b , then the unit vector in the direction of r is 2025If a , b , c are three unit vectors such that a ( b c )= 3 2 b + c 2 and , are the angles between a , c and a , b respectively, then + = 2025 Full Vector Algebra list All MHT CET PYQs