Class 12 Vector Algebra · Short Answer2 Marksdirection_cosines
Class 12 Maths · Vector Algebra · Short Answer #108
Find all vectors equally inclined to the three positive coordinate axes and having magnitude 3√3.
✅ Step-by-Step Solution
Final Answer: ±(3,3,3)
- Equal inclination means all direction cosines equal a common value l.
- Since 3l²=1, l=±1/√3. Multiply each component by magnitude 3√3.
- The two vectors are (3,3,3) and (−3,−3,−3).
📋 CBSE Stepwise Marking Scheme
- [0.5 marks] Equal inclination means all direction cosines equal a common value l.
- [1 mark] Since 3l²=1, l=±1/√3. Multiply each component by magnitude 3√3.
- [0.5 marks] The two vectors are (3,3,3) and (−3,−3,−3).
Master Chapter 10: Vector Algebra
Practise interactive questions, flashcards, visual mind maps, and timed board tests for Vector Algebra.
← Previous Question
Unit vectors a,b have a+b also unit. Find their angle.
Next Question →Unit vectors a,b have √3a−b also unit. Find their angle.
More Practice Questions in Vector Algebra
Related Questions in Vector Algebra
Class 12 Vector Algebra · Mcq Single Correct
Find |a × b|² + (a · b)².
Class 12 Vector Algebra · Mcq Single Correct
Find the area of triangle OAB, where OA = (1,2,3) and OB = (−3,−2,1).
Class 12 Vector Algebra · Mcq Single Correct
For nonzero vectors a,b with angle θ ∈ [0,π], when is a · b ≥ 0?
Class 12 Vector Algebra · Mcq Single Correct
For a vector a, find (a · i)i + (a · j)j + (a · k)k.
Class 12 Vector Algebra · Mcq Single Correct
Which vector has magnitude 9 and the same direction as (1,−2,2)?
Class 12 Vector Algebra · Mcq Single Correct
Find the position vector dividing the segment from 2a − 3b to a + b internally in the ratio…