If `O` is the origin and if the coordinates of any two points `Q_1a n dQ_2` are `(x_1,y_1)a n d(x_2,y_2),` respectively, prove that `O Q_1dotO Q_2cos/_Q_1O Q_2=x_1x_2+y_1y_2dot`

If O is the origin and if the coordinates of any two points Q_1 \ a n d \ Q_2 are (x_1,y_1) \ a n d \ (x_2,y_2), respectively, prove that O Q_1.O Q_2cos/_Q_1O Q_2=x_1x_2+y_1y_2 .

If O is the origin and if the coordinates of any two points Q_1 \ a n d \ Q_2 are (x_1,y_1) \ a n d \ (x_2,y_2), respectively, prove that O Q_1.O Q_2cos/_Q_1O Q_2=x_1x_2+y_1y_2 .

If O is the origin and if the coordinates of any two points Q_(1) and Q_(2) are (x_(1),y_(1)) and (x_(2),y_(2)), respectively,prove that OQ_(1).OQ_(2)cos/_Q_(1)OQ_(2)=x_(1)x_(2)+y_(1)y_(2)

If the coordinates of any two points Q_1 and Q_2 are (x_1,y_1) and (x_2,y_2) , respectively, then prove that OQ_1xxOQ_2cos(angleQ_1OQ_2)=x_1x-2+y-1y_2 , whose O is the origin.

If O be the origin and if coordinates of any two points Q_(1) and Q_(2) be (x_(1),y_(1)) and (x_(2),y_(2)) respectively, prove that overline(OQ_(1))* overline(OQ_(2)) cos angle Q_(1)OQ_(2)=x_(1)x_(2)+y_(1)+y_(2) .

If O be the origin,and if the coordinates of any two points P_(1), and P_(2), be respectively (x_(1),y_(1)) and (x_(2),y_(2)), prove that: OP_(1).OP_(2).cos P_(1)OP_(2)=x_(1)*x_(2)+y_(1)*y_(2)

The co-ordinates of the mid points joining P(x_1,y_1) and Q(x_2,y_2) is….

The coordinates of the midpoint joining P(x_(1),y_(1)) and Q(x_(2),y_(2)) is ....

If the line segment joining the points P(x_1, y_1)a n d Q(x_2, y_2) subtends an angle alpha at the origin O, prove that : O PdotO Q cosalpha=x_1x_2+y_1y_2dot