If O is the origin and `P(x_(1),y_(1)), Q(x_(2),y_(2))` are two points then `POxxOQ sin angle POQ=`

If O be the origin and A(x_(1), y_(1)), B(x_(2), y_(2)) are two points, then what is (OA) (OB) cos angle AOB ?

If O be the origin and if P(x_(1),y_(1)) and P_(2)(x_(2),y_(2)) are two points,the OP_(1)(OP_(2))COS/_P_(1)OP_(2), is equal to

If O is origin,A(x_(1),y_(1)) and B(x_(2),y_(2)) then the circumradius of Delta AOB is

If 'alpha' be the angle subtended by the points P(x_(1),y_(1)) and Q(x_(2),y_(2)) at origin O, Show that OP.OQ.cos alpha=x_(1)x_(2)+y_(1)y_(2)

The coordinate of two points P and Q are (x_(1),y_(1)) and (x_(2),y_(2)) and O is the origin. If the circles are described on OP and OQ as diameters, then the length of their common chord is

If the line joining the points (-x_(1),y_(1)) and (x_(2),y_(2)) subtends a right angle at the point (1,1), then x_(1)+x_(2)+y_(2)+y_(2) is equal to

Let A and B have coordinates (x_(1) , y_(1)) and (x_(2) , y_(2)) respectively . We define the distance between A and B as d (A , B) = max {|x_(2) - x_(1)| , |y_(2) - y_(1)|} If d ( A, O) = 1 , where O is the origin , then the locus of A has an area of

Two fixed points A and B have co-ordinates (x_(1),y_(1)) and (x_(2),y_(2)). A point P moves such that AP is perpendicular to BP, then locus of P is