If the vertices $$P, Q, R$$ of a triangle $$PQR$$ are rational points, which of the following points of the triangle $$PQR$$ is (are) always rational point(s)?
A
centroid ( A rational point is a point both of whose co-ordinates are rational numbers.)
B
incentre. ( A rational point is a point both of whose co-ordinates are rational numbers.)
C
circumcentre ( A rational point is a point both of whose co-ordinates are rational numbers.)
D
orthocentre ( A rational point is a point both of whose co-ordinates are rational numbers.)
2
IIT-JEE 1986
MCQ (More than One Correct Answer)
All points lying inside the triangle formed by the points $$\left( {1,\,3} \right),\,\left( {5,\,0} \right)$$ and $$\left( { - 1,\,2} \right)$$ satisfy
A
$$3x + 2y \ge 0$$
B
$$2x + y - 13 \ge 0$$
C
$$2x - 3y - 12 \le 0$$
D
$$ - 2x + y \ge 0$$
3
IIT-JEE 1985
MCQ (More than One Correct Answer)
Three lines $$px + qy + r = 0$$, $$qx + ry + p = 0$$ and $$rx + py + q = 0$$ are concurrent if
A
$$p + q + r = 0$$
B
$${p^2} + {q^2} + {r^2} = qr + rp + pq$$
C
$${p^3} + {q^3} + {r^3} = 3pqr$$
D
none of these.
Questions Asked from Straight Lines and Pair of Straight Lines
On those following papers in MCQ (Multiple Correct Answer)
Number in Brackets after Paper Indicates No. of Questions
