MHT CET · Maths · Vector Algebra
\(\bar{a}, \overline{\mathrm{~b}}, \overline{\mathrm{c}}\) are nonzero vectors such that \(\bar{a}\) is perpendicular to \(\overline{\mathrm{b}}\) and \(\overline{\mathrm{c}}\), \(|\bar{a}|=1,|\bar{b}|=2,|\bar{c}|=1\) and \(\bar{b} \cdot \bar{c}=1\). There is nonzero vector \(\bar{d}\) coplanar with \(\bar{a}+\overline{\mathrm{b}}\) and \(2 \overline{\mathrm{~b}}-\overline{\mathrm{c}}\). If \(\overline{\mathrm{d}} \cdot \bar{a}=1\), then \(|\overline{\mathrm{d}}|^2=\)
(Note that \(x\) and \(y\) are parameters involved when we write \(d=x(a+b)+y(2 b-c))\)
- A \(13 y^2+14 y+5\)
- B \(y^2+14 y+5\)
- C \(y^2-14 y-5\)
- D \(y^2-14 y+5\)
Answer & Solution
Correct Answer
(A) \(13 y^2+14 y+5\)
Step-by-step Solution
Detailed explanation
\( \bar{d} = x(\bar{a} + \overline{b}) + y(2\overline{b} - \overline{c}) = x\bar{a} + (x+2y)\overline{b} - y\overline{c} \) \( \overline{d} \cdot \bar{a} = 1 \)
See the Complete Solution
Get step-by-step explanations for this and 2.5 Lakh+ more JEE, NEET & CET questions.
- Unlock all solutions
- Practice the full chapter
- Track accuracy across PYQs
4.8 rated on Google Play · 14,000+ reviews
More questions from Maths
- Let \(\mathrm{A}=\lim _{\mathrm{x} \rightarrow 0^{+}}\left(1+\tan ^2 \sqrt{x}\right)^{\frac{1}{2 x}}\), then \(\log _{\mathrm{e}} \mathrm{A}=\)MHT CET 2025 Medium
- Let K be the set of all real values of \(x\), where the function \(\mathrm{f}(x)=\sin |x|-|x|+2(x-\pi) \cos |x|\) is not differentiable. Then the set K isMHT CET 2024 Hard
- The probability that an event A happens in a trial is 0.4 . If three independent trials are made, then the probability that A happens at least once isMHT CET 2025 Easy
- The sum of 10 values is 12 and the sum of their squares is 16.9 , then their standard deviation \((S, D)\) isMHT CET 2022 Easy
- If \(A=\left[\begin{array}{lll}1 & 2 & 3 \\ 1 & 3 & 4 \\ 3 & 4 & 3\end{array}\right]\), then \(A^{-1}=\)MHT CET 2022 Easy
- Let \(\mathrm{a}, \mathrm{b}, \mathrm{c}\) be distinct non-negative umbers. If the vectors \(a \hat{i}+a \hat{j}+c \hat{k}, \hat{i}+\hat{k}\) and \(c \hat{i}+c \hat{j}+b \hat{k}\) lie in a plane, then c isMHT CET 2022 Easy
More PYQs from MHT CET
- The joint equation of the lines through the origin trisecting angles in first and third equadrant isMHT CET 2020 Medium
- Which among the following is an example of branched chain polymer?MHT CET 2023 Easy
- Calculate the cryoscopic constant of solvent if depression in freezing point of 0.4 m solution of nonvolatile solute is 1.8 K .MHT CET 2025 Easy
- What is vapour density of \(\mathrm{O}_2\) gas?MHT CET 2025 Easy
- In a capactive circuit, the reactance of capacitor at frequency 'f' is ' \(\mathrm{X}_{\mathrm{c}}{ }^{\prime}\). What will be
its reactance at frequency \(4 \mathrm{f} ?\)MHT CET 2020 Easy - The solution of \(r d x+\left(x-r^{2}\right) d r=0\) isMHT CET 2020 Easy