Simplified circle's locus!

Geometry Level 2

A point 'P' moves such that tangents drawn from it through the circle $x^2+y^2=r^2$ . always remain perpendicular to each other. Another point 'Q' moves between locus of point 'P' and given circle such that it covers maximum area and always remain equidistant from a fixed point 'R'. Find locus of point 'R' ?

x+y=r√2-1 x^2+y^2=r^2 (1/√2) x^2+y^2=r^2 (√2-1) x^2+y^2=r^2 (3-2√2)/4