Point P (x, y) is a point in the plane rectangular coordinate system. If XY > 0, then point P is in; if xy = 0, then point P is in; if the square of X + the square of y = 0, then point P is in

Point P (x, y) is a point in the plane rectangular coordinate system. If XY > 0, then point P is in; if xy = 0, then point P is in; if the square of X + the square of y = 0, then point P is in

First and fourth,
x. On the y-axis
On the origin

Xy = m, 1 / 2 of x ^ 2 + 1 / 2 of Y ^ 2 = n, then what is (X-Y) ^ 2 equal to

X ^ 1 / 2 + y ^ 1 / 2 = n,
So the square of both sides is: x + y + 2x ^ (1 / 2) y ^ (1 / 2) = n ^ 2
So x + y = n ^ 2-2m ^ (1 / 2)
So (X-Y) ^ 2 = (x + y) ^ 2-4xy = n ^ 4 + 4N ^ 2m ^ (1 / 2)