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If the line segment joining the points P...

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`

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RD SHARMA ENGLISH-BRIEF REVIEW OF CARTESIAN SYSTEM OF RECTANGULAR COORDINATES-All Questions
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  2. Two vertices of a triangle are (3,-5)a n d(-7,4)dot If its centroid is...

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  3. If the line segment joining the points P(x1, y1)a n d\ Q(x2, y2) subte...

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  4. Four points A(6,3),\ B(-3,5),\ C(4,-2)a n d\ D(x ,3x) are given in s...

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  5. The points A(2,0),\ B(9,1),\ C(11 ,6)a n d\ D(4,4) are the vertices...

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  7. The base of an equilateral triangle with side 2a lies along the y-ax...

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  8. Find the distance between P(x1,\ y1)a n d\ Q(x2, y2) when i. P Q is p...

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  9. Find a point on the x-axis, which is equidistant from the point (7,...

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  10. Find the equation to the locus of a point which moves so that the s...

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  11. Find the locus of the point of intersection of lines xcosalpha+ysin...

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  12. A rod of length l slides with its ends on two perpendicular lines. ...

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  13. If O is the origin and Q is a variable points on x^2=4ydot Find the ...

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  14. Find the locus of a point equidistant from the point (2,4) and the ...

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  15. Find the locus of a point such that the sum of its distances from the ...

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  16. Find the locus of a point which is equidistant from (1,3) and x-axi...

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  17. Find the locus of a point which moves such that its distance from t...

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  18. Find the locus of a point such that the line segments having end po...

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  19. If A(-1,1)a n d\ B(2,3) are two fixed points, find the locus of a po...

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  20. If O is the origin and Q is a variable point on y^2=xdot Find the l...

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