Email
Chat with tutors
logo

Ask Questions, Get Answers

X
 
Questions  >>  JEEMAIN and NEET  >>  Mathematics  >>  Class11  >>  3-D Geometry
Answer
Comment
Share
Q)

If the planes x=cy+bz,y=az+cx,z=bx+ay pass through a line then a2+b2+c2+2abc=?

(a)0(b)1(c)2(d)1.</p

Ans is 1.
Since, x=cy+bz----(1)
y=az+cx----(2)
and z=bx+ay----(3)
by cancellation z from (1)&(2) by help (3) we get,
(1-b^2)x=(c+ab) y
=>x/y=(c+ab)/(1-b^2) ----(4)
&(1-a^2)y=(c+ab) x
=>y/x=(c+ab)/(1-a^2) -----(5)
now by multiplying(4)&(5) we get,
1=(c^2+2abc+a^2b^2)/(1-a^2-b^2+a^2b^2)
=> a^2+b^2+c^2+2abc=1.
Home Ask Tuition Questions
Your payment for is successful.
Continue
...