✓ Board-verified
Mathematics · 2025 · 1 mark
CBSE 2025 · Region 1 · Set 2 · Q2
If α = i -4 j +9 k and β =2 i -8 j +λ k are two mutually parallel vectors, then λ is equal to:
If $\displaystyle \vec{\alpha}=\hat{i}-4 \hat{j}+9 \hat{k}$ and $\displaystyle \vec{\beta}=2 \hat{i}-8 \hat{j}+\lambda \hat{k}$ are two mutually parallel vectors, then $\displaystyle \lambda$ is equal to:
Official answer
(B)
$\displaystyle 18$
All Vector Algebra questions2025 question paperNCERT solutions: Vector AlgebraPractice Vector Algebra →
More from Vector Algebra
- If a and b are two non-collinear vectors, then find x, such that α=(x-2) a+ b and β=(3+2 x) a-2 b are collinear.2025
- Three friends A, B and C move out from the same location O at the same time in three different directions to reach their destinations. They move out…2025
- If a+ b+ c= 0 such that | a|=3,| b|=5,| c|=7, then find the angle between a and b. OR If a and b are unit vectors inclined with each other at an…2025
- Find a vector of magnitude 4 units perpendicular to each of the vectors 2 i- j+ k and i+ j- k and hence verify your answer.2024
- The position vectors of points P and Q are p and q respectively. The point R divides line segment PQ in the ratio 3: 1 and S is the mid-point of line…2024
- If | a × b|=√3 and a · b=-3, then angle between a and b is2023
- Let p and q be two unit vectors and α be the angle between them. Then ( p+ q) will be a unit vector for what value of α?2025
- Using vectors, find the value of 'b' if the points A(-1, -1, 2), B(2, b, 5) and C(3, 11, 6) are collinear. Also, determine the ratio in which the…2022
CBSE Class 12 Mathematics past-paper question from the 2025 board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.