Get Answers to all your Questions

header-bg qa

If the plane \mathrm{ P} passes through the intersection of two mutually perpendicular planes \mathrm{ 2 x+k y-5 z=1} and\mathrm{ 3 k x-k y+z=5,} \mathrm{ k<3} and intercepts a unit length on positive \mathrm{ x}-axis, then the intercept made by the plane \mathrm{ P} on the \mathrm{ y}-axis is

Option: 1

\frac{1}{11}


Option: 2

\frac{5}{11}


Option: 3

6


Option: 4

7


Answers (1)

best_answer

Two given plane mutually perpendicular

\mathrm{2(3 k)+k(-k)+(-5) 1=0 }\\

\mathrm{k=1,5}

\mathrm{but\; k<3 \quad so\; k=1}

Plane passing through these phase is

\mathrm{2 x+4=5 z-1+\lambda(3 x-y+z-5)=0} \\

\mathrm{\frac{x}{\frac{5 \lambda+1}{2+3 \lambda}}+\frac{y}{\frac{5 \lambda+1}{1-\lambda}}+\frac{z}{\frac{5 \lambda+1}{\lambda-5}}=1 }\\

\mathrm{\text { given } \frac{5 \lambda+1}{2+3 \lambda}=1 \Rightarrow \lambda=\frac{1}{2}}

\mathrm{So\; intercept\; on\; y-axis =\frac{5 \lambda+1}{1-\lambda}=7}

Hence correct option is 4

 

Posted by

Gautam harsolia

View full answer

JEE Main high-scoring chapters and topics

Study 40% syllabus and score up to 100% marks in JEE