Browse by Stream
QnA
Home
QnA
Go To Your Study Dashboard

Get Answers to all your Questions

header-bg qa

The d.r. of normal to the plane through (1, 0, 0), (0, 1, 0) which makes an angle \pi /4 with plane x+y=3  are

  • Option 1)

    1,\sqrt{2},1

  • Option 2)

    1,1,\sqrt{2}

  • Option 3)

    1,1,2

  • Option 4)

    \sqrt{2},1,1

 

Answers (1)

best_answer

As we learnt in 

Direction Ratios -

If l,m,n are direction cosines then three numbers a,b,c propotional to l,m,n are called direction cosines. 

a=kl,b=km,c=kn

 

-

 

 Plane through (1,0,0) is 

a(x-1)+by +cz= 0

It passes though (0,1,0) 

We get, -a +b =0

\Rightarrow a=b

\cos 45^{0}= \frac{a+a}{\sqrt{2(2a^{2}+c^{2})}}

\Rightarrow c= \sqrt{2}a

DRs of normal are (a,a, \sqrt{2}a)

(1,1, \sqrt{2})

 


Option 1)

1,\sqrt{2},1

Incorrect option

Option 2)

1,1,\sqrt{2}

Correct option

Option 3)

1,1,2

Incorrect option

Option 4)

\sqrt{2},1,1

Incorrect option

Posted by

divya.saini

View full answer

JEE Main high-scoring chapters and topics

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

Similar Questions

Trending Articles/News

anam-khan

JEE Main 2024 Topper: Farmer’s son Gajare Nilkrishna says ‘keep questioning until you understand’
anam-khan

NIT Puducherry Cut-off 2024: Computer Science and Engineering had highest closing rank last year
anam-khan

What after JEE Main results 2024? All you need to know about JEE Adv, CSAB, JoSAA counselling

Latest Question