Equation of normal to the hyperbola xy=c2 at the point P(x1,y1) is xx1−yy1=x12−y12.
If P(x1,y1) is such that x21a2−y21b2> 1.
Then the point P situates outside the standard hyperbola x21a2−y21b2>=1.
The equation of the chord of the circle x2+y2=a2 having (x1,y1) as its mid-point is