A. x2+y2=(a+b)2

B. x2+y2=(a-b)2

C. x2-y2=(a+b)2

D. x2-y2=(a-b)2

The locus of the middle point of chords of the ellipse x^{2}/a^{2}+y^{2}/b^{2}=1 whose pole lies on the auxiliary circle is

The midpoint of a chord 4x+5y-13=0 of the ellipse 2x^{2}+5y^{2}=20 is

The equation of the chord of the ellipse 2x^{2}+3y^{2}=6 having (1, -1) as its midpoint is

The locus of the poles of chords of the ellipse x^{2}/a^{2}+y^{2}/b^{2}=1 which touch The locus of the poles w.r.t the ellipse x^{2}/α^{2}+y^{2}/β^{2}=1 is

The tangent and normal to the ellipse 4x^{2}+9y^{2} =36 at a point P on it meets the major axis in Q nd R respectively. If QR=4, then the eccentric angle of P is