• Support PF! Buy your school textbooks, materials and every day products via PF Here!

Implicit derivative of function, calc 3

  • Thread starter tnutty
  • Start date
327
1
1. Homework Statement


Find dy/dx ;

sqrt(xy) = 1 + yx^2
or
0 = 1 + yx^2 - sqrt(xy)

Definition :

dy/dx = - F_x / F_y;

A = F_x = 2xy - 1/2 (xy)^-0.5 * y
B = F_y = x^2 - 1/2(xy)^-0.5 * x

Then dy/dx = -A / B

But the answer according to the book, is this :

4(xy)^-1.5 - y
--------------
x - 2x^2/(sqrt(xy))
 

Dick

Science Advisor
Homework Helper
26,258
618
They just multiplied numerator and denominator by 2*sqrt(xy).
 

Related Threads for: Implicit derivative of function, calc 3

Replies
5
Views
5K
Replies
4
Views
1K
Replies
3
Views
4K
Replies
6
Views
4K
  • Posted
Replies
1
Views
11K
Replies
6
Views
3K
Replies
4
Views
4K

Physics Forums Values

We Value Quality
• Topics based on mainstream science
• Proper English grammar and spelling
We Value Civility
• Positive and compassionate attitudes
• Patience while debating
We Value Productivity
• Disciplined to remain on-topic
• Recognition of own weaknesses
• Solo and co-op problem solving
Top