How do you determine whether the graph of absy=xy|y|=xy is symmetric with respect to the x axis, y axis or neither?

1 Answer
Apr 19, 2018

|y|=xy|y|=xy is neither symmetric w.r.t. xx axis nor w.r.t. yy axis

Explanation:

If a function is symmetric w.r.t. xx-axis, then if (x_1,y_1)(x1,y1) satisfies the equation, so does (x_1,-y_1)(x1,y1)

If (x_1,y_1)(x1,y1) satisfies equation then |y_1|=x_1y_1|y1|=x1y1

and for (x_1,-y_1)(x1,y1), |-y_1|=|y_1||y1|=|y1| and x_1*(-y_1)=-x_1y_1x1(y1)=x1y1

Hence |y|=xy|y|=xy is not symmetric w.r.t. xx axis.

If a function is symmetric w.r.t. yy-axis, then if (x_1,y_1)(x1,y1) satisfies the equation, so does (-x_1,y_1)(x1,y1)

If (x_1,y_1)(x1,y1) satisfies equation then |y_1|=x_1y_1|y1|=x1y1

and for (-x_1,y_1)(x1,y1), |y_1|=|y_1||y1|=|y1| and (-x_1)*y_1=-x_1y_1(x1)y1=x1y1

Hence |y|=xy|y|=xy is not symmetric w.r.t. yy axis.