Equation of the normal to the curve Watch

trayder
Badges: 0
Rep:
?
#1
Report Thread starter 10 years ago
#1
Is the equation of the normal to the curve at the origin always y=x. I am working on this question, a curve has equation y=3x/2x-3. The question is find the equation of the normal to the curve at the origin. the answer in the book is y=x, but i got y=3x. Can someone help please. Thank you
0
quote
reply
Mr M
  • Community Assistant
Badges: 20
Rep:
?
#2
Report 10 years ago
#2
The equation of the normal at the origin is certainly NOT always y=x.

However, it will always be of the form y=kx.

k will be the negative reciprocal of the gradient of the curve at the origin.
0
quote
reply
trayder
Badges: 0
Rep:
?
#3
Report Thread starter 10 years ago
#3
I did that but i get a gradient of 3. which is not the correct answer.
0
quote
reply
trayder
Badges: 0
Rep:
?
#4
Report Thread starter 10 years ago
#4
Ive managed to work it out now. Thanks
0
quote
reply
Mr M
  • Community Assistant
Badges: 20
Rep:
?
#5
Report 10 years ago
#5
(Original post by trayder)
I did that but i get a gradient of 3. which is not the correct answer.
The gradient of the curve is -1.

Did you use the quotient rule?

Edit: Ok, no problem.
0
quote
reply
X

Quick Reply

Attached files
Write a reply...
Reply
new posts
Latest
My Feed

See more of what you like on
The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

Personalise

University open days

  • University of Lincoln
    Mini Open Day at the Brayford Campus Undergraduate
    Wed, 19 Dec '18
  • University of East Anglia
    UEA Mini Open Day Undergraduate
    Fri, 4 Jan '19
  • Bournemouth University
    Undergraduate Mini Open Day Undergraduate
    Wed, 9 Jan '19

Were you ever put in isolation at school?

Yes (221)
28.01%
No (568)
71.99%

Watched Threads

View All