Important points on A.P.

Important points on G.P.

S_n in A.P.=

The abscissa of the three points P , Q , R of an ellipse, one of whose focus is S , are in A.P . Prove that the focal distances of the three points are also in A.P .

The first, fourth and thirteenth term of an A.P. are in G.P. If the first term of the A.P. is 3, find the A.P.

A(1, 4) and B (4, 8) are two points. P is a point on AB such that AP=AB+BP . If AP=10 , find the coordinates of P .

A(1, 4) and B (4, 8) are two points. P is a point on AB such that AP=AB+BP . If AP=10 , find the coordinates of P .

If S be the focus and R the point of intersection of the tangents to a parabola at two points P and Q , then PS, RS and QS are in : (A) A.P. (B) G.P. (C) H.P. (D) none of these

The sum of the first p terms of an A.P. is q and the sum of the first q terms of the same A.P. is p. Find the sum of the first (p+q) terms of the A.P.

The sequence -10,-6,-2,2,….. a)is an A.P, Reason d=-16 b)is an A.P, Reason d=-4 c)is an A.P, Reason d= 4 d)is not an A.P.