A curve is given parametrically by x=ct, y=\frac{c}{t}. Show that an equation of the tangent to the curve at the point (ct, \frac{c}{t}) is x+t^2y=2ct(solved)

Show that an equation of the normal to the parabola with equation y^2=4ax at the point P (at^2,2at) is y+tx=2at+at^3
This normal meets the parabola again at the point Q (as^2, 2as)
Show that s+t+ \frac{2}{t}=0

Could not show it, Stuck at: \frac{2}{t}\pm2a(t^2+1) Help