# 2 different dy/dx of xy=c^2

1. Oct 1, 2009

### vikcool812

I have a relation xy=c2 , if i apply implicit differentiation to both sides i get dy/dx =-y/x , but if i write the same thing as y=c2/x , then dy/dx comes out to be -c2/x2 , whats going wrong ??????

2. Oct 1, 2009

### Office_Shredder

Staff Emeritus
If xy=c2, then y=c2/x. So -y/x = -c2/x2 You got the same answer, just in a different form

3. Oct 1, 2009

### quasar987

Nothing since -y/x = -c²/x2 !