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**qazxsw11111** Hi everyone. I am familiar with the graphing of y² graph which is essentially sqrt of the graph then reflected in the x-axis. However, I am confused at the points where the y= graph cuts the x-axis. According to differentiation, the gradient of the sqrt y graph should have a sqrt y at the denominator using quotient rule. If y=0, the gradient should be infinity. However, I do see some graphs with some other shapes (some crossing, some flat) at the x-axis so Im wondering about this. Hope someone can help to clarify my problems.