If the line segment joining the points `A(a,b) and B (c, d)` subtends a right angle at the origin, show that `ac+bd=0`

If the segment joining the points (a,b),(c,d) subtends a right angle at the origin,then

If the line segment joining the points A(a,b) and B(a, -b) subtends an angle theta at the origin, show that cos theta = (a^2 - b^2)/(a^2 +b^2) .

If the line segment joining the point A(a,b) and B(c,d) subtends an angle theta at the origin.Prove that cos theta=(ac+bd)/(sqrt((a^(2)+b^(2))*(c^(2)+d^(2))))

If the line segment joining the points A(a,b) and B(c,d) subtends an angle theta at the origin, then costheta is equal to

If the segments joining the points A(a,b) and B(c,d) subtends an angle theta at the origin,prove that :theta=(ac+bd)/((a^(2)+b^(2))(c^(2)+d^(2)))

Find the locus of a point such that the line segments having end points (2,0) and (-2,0) subtend a right angle at that point.

The mid - point of the line segment joining the points A(a,0) and B(0,b) is ………. .

If the line segment on lx+my=n^(2) intercepted by the curve y^(2)=ax subtends a right angle at the origin,then

If the line segment joining the points A(7, p, 2) and B(q, -2, 5) be parallel to the line segment joining the points C(2, -3, 5) and D(-6, -15, 11), find the value of p and q.

The point at which the line segment joining A(1, 1) and B (5, 5) subtends an obtuse angle is