How do I eliminate the arbitrary constant in the equation y = ax^2 -1?
The answer at the back of the book is 2y = x(dy/dx)-2 however I don't understand how they arrived at this.
Here is my attempt:
y = ax^2 -1
dy/dx = 2ax
(dy/dx) (1/2x) = a
therefore y = (dy/dx) (1/2x)x^2 - 1
Where did I go wrong?