## ParthKohli 2 years ago What are the roots of $$y = x^2$$?

1. goformit100

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2. ParthKohli

A friend of mine suggests that people don't think that zero is a real solution.

3. Mertsj

The roots are the x intercepts. Set y to 0 and you will see that x=0 is a double root which indicates a point of tangency to the x axis at x = 0

4. Mertsj

People can think whatever they want. Doesn't make it true.

5. ParthKohli

$x^2 = 0 \implies x = 0$

6. goformit100

You friend is a crazy guy.

7. ParthKohli

OK, thank you!

8. Mertsj

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9. Mertsj

yw

10. ParthKohli

Thanks, enough to explain.

11. UnkleRhaukus

$y=x^2$$x^2-y=0$$x_{1,2}=\frac{0\pm\sqrt{0^2-4(1)(-y)}}{2(1)}\\=\frac{\pm\sqrt{4y}}{2}\\ =\pm \sqrt y$

12. ParthKohli

Nice solution, but by "roots", I meant zeroes :-)

13. UnkleRhaukus

$0=\pm\sqrt0$

14. ParthKohli

Ah, lol!