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)
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