JEE Advanced · Mathematics · 31. 3D Geometry
The equation of a plane passing through the line of intersection of the planes \(x+2 y+3 z=2\) and \(x-y+z=3\)
and at a distance \(\frac{2}{\sqrt{3}}\) from the point \((3,1,-1)\) is
- A \(5 x-11 y+z=17\)
- B \(\sqrt{2} x+y=3 \sqrt{2}-1\)
- C \(x+y+z=\sqrt{3}\)
- D \(x-\sqrt{2} y=1-\sqrt{2}\)
Answer & Solution
Correct Answer
(A) \(5 x-11 y+z=17\)
Step-by-step Solution
Detailed explanation
Equation of the plane passing through the intersection line of given planes is
\(\begin{array}{ll}
& (x+2 y+3 z-2)+\lambda(x-y+z-3)=0 \\
\text { or } & (1+\lambda) x+(2-\lambda) y+(3+\lambda) z+(-2-3 \lambda)=0
\end{array}\)
\(\because \quad\) Its distance from the point \((3,1,-1)\) is \(\frac{2}{\sqrt{3}}\)
\(\begin{array}{l}
\therefore\left|\frac{3(1+\lambda)+1(2-\lambda)-1(3+\lambda)+(-2-3 \lambda)}{\sqrt{(1+\lambda)^{2}+(2-\lambda)^{2}+(3+\lambda)^{2}}}\right|=\frac{2}{\sqrt{3}} \\
\Rightarrow\left|\frac{-2 \lambda}{\sqrt{3 \lambda^{2}+4 \lambda+14}}\right|=\frac{2}{\sqrt{3}} \\
\Rightarrow 3 \lambda^{2}+4 \lambda+14=3 \lambda^{2} \Rightarrow \lambda=-\frac{7}{2}
\end{array}\)
\(\therefore\) Required equation of plane is
\((x+2 y+3 z-2)-\frac{7}{2}(x-y+z-3)=0\)
or \(5 x-11 y+z=17\)
\(\begin{array}{ll}
& (x+2 y+3 z-2)+\lambda(x-y+z-3)=0 \\
\text { or } & (1+\lambda) x+(2-\lambda) y+(3+\lambda) z+(-2-3 \lambda)=0
\end{array}\)
\(\because \quad\) Its distance from the point \((3,1,-1)\) is \(\frac{2}{\sqrt{3}}\)
\(\begin{array}{l}
\therefore\left|\frac{3(1+\lambda)+1(2-\lambda)-1(3+\lambda)+(-2-3 \lambda)}{\sqrt{(1+\lambda)^{2}+(2-\lambda)^{2}+(3+\lambda)^{2}}}\right|=\frac{2}{\sqrt{3}} \\
\Rightarrow\left|\frac{-2 \lambda}{\sqrt{3 \lambda^{2}+4 \lambda+14}}\right|=\frac{2}{\sqrt{3}} \\
\Rightarrow 3 \lambda^{2}+4 \lambda+14=3 \lambda^{2} \Rightarrow \lambda=-\frac{7}{2}
\end{array}\)
\(\therefore\) Required equation of plane is
\((x+2 y+3 z-2)-\frac{7}{2}(x-y+z-3)=0\)
or \(5 x-11 y+z=17\)
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 Mathematics
- Let the circles and intersect at the points and Suppose that another circle satisfies the following conditions:
centre of is collinear with the centres of and
and both lie inside and
touches at and at
Let the line through and intersect at and and let a common tangent of and be a tangent to the parabola
There are some expression given in the List- whose values are given in List- below:
List- I List- II
Which of the following is the only INCORRECT combination?JEE Advanced 2019 Medium - Paragraph:
Let \(p, q\) be integers and let \(\alpha, \beta\) be the roots of the equation, \(x^{2}-x-1=0\), where \(\alpha \neq \beta\). For \(n=0,1,2, \ldots\), let \(a_{n}=p \alpha^{n}+q \beta^{n}\)
FACT: If \(a\) and \(b\) are rational numbers and \(a+b \sqrt{5}=0\), then \(a=0=b\).
Question:
If \(a_{4}=28\), then \(p+2 q=\)JEE Advanced 2017 Medium - The smallest value of \(k\), for which both the roots of the equation \(x^2-8 k x+16\left(k^2-k+1\right)=0\) are real, distinct and have values atleast 4 , isJEE Advanced 2009 Easy
- Paragraph:
Consider the functions defined implicitly by the equation \(y^3-3 y+x=0\) on various intervals in the real line. If \(x \in(-\infty,-2) \cup(2, \infty)\), the equation implicitly defines a unique real valued differentiable function \(y=f(x)\). If \(x \in(-2,2)\), the equation implicitly defines a unique real valued differentiable function \(y=g(x)\), satisfying \(g(0)=0\).Question:
If \(f(-10 \sqrt{2})=2 \sqrt{2}\), then \(f^{\prime \prime}(-10 \sqrt{2})\) is equal toJEE Advanced 2008 Medium - Two adjacent sides of a parallelogram \(A B C D\) are given by \(\overrightarrow{\mathbf{A B}}=2 \hat{\mathbf{i}}+10 \hat{\mathbf{j}}+11 \hat{\mathbf{k}}\) and \(\overrightarrow{\mathbf{A D}}=-\hat{\mathbf{i}}+2 \hat{\mathbf{j}}+2 \hat{\mathbf{k}}\). The side \(A D\) is rotated by an acute angle \(\alpha\) in the plane of the parallelogram so that \(A D\) becomes \(A D^{\prime}\). If \(A D^{\prime}\) makes a right angle with the side \(A B\), then the cosine of the angle \(\alpha\) is given byJEE Advanced 2010 Easy
- Let \(M\) and \(N\) be two \(3 \times 3\) non-singular skew-symmetric matrices such that \(M N=N M\). If \(P^T\) denotes the transpose of \(P\), then \(M^2 N^2\left(M^T N\right)^{-1}\left(M N^{-1}\right)^T\) is equal toJEE Advanced 2011 Hard
More PYQs from JEE Advanced
- A solid glass sphere of refractive index \(n=\sqrt{3}\) and radius \(R\) contains a spherical air cavity of radius \(\frac{\mathrm{R}}{2}\), as shown in the figure. A very thin glass layer is present at the point O so that the air cavity (refractive index \(n=1\)) remains inside the glass sphere. An unpolarized, unidirectional and monochromatic light source \(S\) emits a light ray from a point inside the glass sphere towards the periphery of the glass sphere. If the light is reflected from the point O and is fully polarized, then the angle of incidence at the inner surface of the glass sphere is \(\theta\). The value of \(\sin \theta\) is ______ [given : θ > 30°]
JEE Advanced 2025 Hard - A circuit is connected as shown in the figure with the switch \(S\) open. When the switch is closed, the total amount of charge that flows from \(Y\) to \(X\) is
JEE Advanced 2007 Medium - Inradius of a circle which is inscribed in an isosceles triangle one of whose angle is \(2 \pi / 3\), is \(\sqrt{3}\), then area of triangle isJEE Advanced 2006 Easy
- A solution when diluted with \(\mathrm{H}_2 \mathrm{O}\) and boiled, it gives a white precipitate. On addition of excess \(\mathrm{NH}_4 \mathrm{Cl} / \mathrm{NH}_4 \mathrm{OH}\), the volume of precipitate decreases leaving behind a white gelatinous precipitate. Identify the precipitate which dissolves in \(\mathrm{NH}_4 \mathrm{OH} / \mathrm{NH}_4 \mathrm{Cl}\).JEE Advanced 2006 Hard
- For \(0 < \theta < \frac{\pi}{2}\), the solution(s) of \(\sum_{m=1}^6 \operatorname{cosec}\left[\theta+\frac{(m-1) \pi}{4}\right]\) \(\operatorname{cosec}\left(\theta+\frac{m \pi}{4}\right)=4 \sqrt{2}\) is/areJEE Advanced 2009 Hard
- Let and be positive real numbers. Suppose and are adjacent sides of a parallelogram Let and be the projection vectors of along and , respectively. If and if the area of the parallelogram is then which of the following statements is/are TRUE?JEE Advanced 2020 Medium