UrbanPro

Take Class I-V Tuition from the Best Tutors

  • Affordable fees
  • 1-1 or Group class
  • Flexible Timings
  • Verified Tutors

Search in

If l,m,n be three real numbers proportional to the direction cosines of a line L.then l²+m²+n²=1

Asked by Last Modified  

11 Answers

Follow 0
Answer

Please enter your answer

Free Mathematics Teaching and Guidance to Very Weak Students in study

YES
Comments

1541252

yes true
Comments

Genuine artist in teaching mathematics in a very very simple yet exciting way

If a, b, c are three numbers proportional to the direction cosine l, m, n of a straight line, then a, b, c are called its direction ratios. They are also called direction numbers or direction components. Hence by definition, we have 1/a = m/b = n/c = k (say) => l=ak, m=bk, n=ck => k2(a2...
read more
If a, b, c are three numbers proportional to the direction cosine l, m, n of a straight line, then a, b, c are called its direction ratios. They are also called direction numbers or direction components. Hence by definition, we have 1/a = m/b = n/c = k (say) => l=ak, m=bk, n=ck => k2(a2 + b2 + c2) = l2 + m2 + n2=1 => k = ± 1 / ?a2 + b2 + c2 = ± 1/??a2 l = ± a/??a2. Similarly m = ± b/??a2 and n = ± n/??a2 where the same sign either positive or negative is to be chosen throughout. Example: If 2, – 3, 6 be the direction ratios, then the actual direction cosines are 2/7, –3/7, 6/7. Note: Direction cosines of a line are unique but direction ratios of a line in no way unique but can be infinite. read less
Comments

Tutor

If l , m and n are the direction cosines of any line, then l² + m² + n² = 1 Proof: Let OP be drawn through the origin parallel to the given line so that l , m , n are the cosines of the angles which OP makes with OX, OY and OZ respectively. Let (x, y , z) be the co-ordinates of any point P on this...
read more
If l , m and n are the direction cosines of any line, then l² + m² + n² = 1 Proof: Let OP be drawn through the origin parallel to the given line so that l , m , n are the cosines of the angles which OP makes with OX, OY and OZ respectively. Let (x, y , z) be the co-ordinates of any point P on this line. Let OP = r , then x = lr , y = mr , z = nr Squaring and adding , we obtain x² + y² + z² = ( l² + m² + n²) r² l² + m² + n² = (x² + y² + z²) / r² but r² = OP² =(x² + y² + z²) Thus l² + m² + n² = 1 Proved. read less
Comments

English teacher with 5 years of experience in teaching,• Instructed students in English language arts, including writing, reading comprehension, speaking, listening and understanding

RELATION BETWEEN DIRECTION COSINES: If l , m and n are the direction cosines of any line, then l² + m² + n² = 1 Proof: Let OP be drawn through the origin parallel to the given line so that l , m , n are the cosines of the angles which OP makes with OX, OY and OZ respectively. Let (x, y , z) be the...
read more
RELATION BETWEEN DIRECTION COSINES: If l , m and n are the direction cosines of any line, then l² + m² + n² = 1 Proof: Let OP be drawn through the origin parallel to the given line so that l , m , n are the cosines of the angles which OP makes with OX, OY and OZ respectively. Let (x, y , z) be the co-ordinates of any point P on this line. Let OP = r , then x = lr , y = mr , z = nr Squaring and adding , we obtain x² + y² + z² = ( l² + m² + n²) r² l² + m² + n² = (x² + y² + z²) / r² but r² = OP² =(x² + y² + z²) Thus l² + m² + n² = 1 Proved. read less
Comments

Tutor

yes
Comments

Home tutor available for 1st to 10th class(Mathematics)

yes , l²+m²+n² is equal to 1
Comments

Tutor

Direction cosines can be written in terms of direction ratios. l = a/sqrt(a^2+b^2+c^2), m = b/sqrt(a^2+b^2+c^2) n = c/sqrt(a^2+b^2+c^2) So, l^2+m^2+n^2 = (a^2+b^2+c^2)/(a^2+b^2+c^2) =1
Comments

Tutor

yes
Comments

Target learning

yups true.
Comments

View 9 more Answers

Related Questions

I am a tuition teacher now I want to be a school teacher but I have completed my studies up to B.com in commerce can I go for B.A in arts. Isn't it possible to go for B.A exams?
Dear Priya, You have done B.com, and in order to get qualified as a teacher, you need to do B.Ed. If there is any specific subject which you need to teach in the field of arts then you need to check with...
Priya
What is the meaning of WORLD?
The earth together with all of its people and countries...
Dinesh Krishnan
How much should I charge for 1-5 per hour & monthly (weekly 3 class)? How much should I charge for 6-8 per hour & monthly (weekly 3 class)?
Start with low amount. Once you build a reputation, you can charge according to market.
Rajeev Kumar Yadav
what is good for our body to build muscles?
It again depends on your requirement you want to build mass or lean muscle. For Mass working out at gym will be more and you need to take some food with fat content to build muscle. For Lean Muslce you...
Ravi Ranjan

Now ask question in any of the 1000+ Categories, and get Answers from Tutors and Trainers on UrbanPro.com

Ask a Question

Related Lessons


Value of Sports
The value of sports and games is recognised by all educationists today. Books develop our mind but games develop our body a sound mind is always there in a sound body. Sports make our body stout (stronger)...

Mrs.Satinder D.

0 0
0

Learn Hindi Grammar
Uses of Hindi Grammar:In Hindi- How to address different people?

I blame you, Mom.
I blame you, if you can’t tell me of the reasons.I blame you, if you force me to memorize.I blame you, if I score low. Spellings are a torture for native & non-native speakers....

French Pronouns and Conjugation and Être verb
In this lesson, the Verb Être= to be (present tense) with pronouns has been explained.Je suis= I amTu es= You areil/elle/on est= He/she/it isnous sommes= we arevous êtes= you areils/elles sont=...

Recommended Articles

Well, teachers are considered to be the shaper of society. They stand in a very high position not just because of their job role but for an underlying sense of respect that has been associated with the profession since ancient times. The most exciting thing about this profession is that a good teacher can help the students...

Read full article >

Many believe that history is a subject to study the past. To some extent, it is true but broadly, speaking history is a lot more than that. This subject lets us know about the glorious historical events that took place and make us proud of them. Besides, it also alerts us about our mistakes, the lessons we learned from...

Read full article >

A tutor can be a real guide for a child and help him/her prosper academically and personally. However before you get down to the imperative question of - Does your child needs a tutor... you need to understand the significance of what exactly a tutor can do for your child. A tutor is a teacher who guides the student in...

Read full article >

Mathematics is one of the most important subjects students need to learn to have a great career ahead and solve many mathematical problems we come across every day. Mathematics is a popular subject because of its utility in every aspect of life. Without maths, leading an everyday and functional life is nearly impossible....

Read full article >

Looking for Class I-V Tuition ?

Learn from the Best Tutors on UrbanPro

Are you a Tutor or Training Institute?

Join UrbanPro Today to find students near you
X

Looking for Class I-V Tuition Classes?

The best tutors for Class I-V Tuition Classes are on UrbanPro

  • Select the best Tutor
  • Book & Attend a Free Demo
  • Pay and start Learning

Take Class I-V Tuition with the Best Tutors

The best Tutors for Class I-V Tuition Classes are on UrbanPro

This website uses cookies

We use cookies to improve user experience. Choose what cookies you allow us to use. You can read more about our Cookie Policy in our Privacy Policy

Accept All
Decline All

UrbanPro.com is India's largest network of most trusted tutors and institutes. Over 55 lakh students rely on UrbanPro.com, to fulfill their learning requirements across 1,000+ categories. Using UrbanPro.com, parents, and students can compare multiple Tutors and Institutes and choose the one that best suits their requirements. More than 7.5 lakh verified Tutors and Institutes are helping millions of students every day and growing their tutoring business on UrbanPro.com. Whether you are looking for a tutor to learn mathematics, a German language trainer to brush up your German language skills or an institute to upgrade your IT skills, we have got the best selection of Tutors and Training Institutes for you. Read more