[填空题]
The equation of a cu dg6a+;8fkcfe2e9c/fnc pi hb :y04drph *w,mrve is y= p nuk57z0mkq.g6wht/ fid89s1-$\frac{9}{x}$.
1.Find the equation of the tangent to the curve at x=3.
y=ax-b;a= , b= .
2.Find the coordinates of the points on the curve where the gradient is $\frac{1}{4}$.
the points are (a,-$\frac{b}{2}) and (-6,$\frac{c}{d}$).
a= , b= , c= , d= .
