Cylindrical Co-ordinate Question

[ZedCar]

Homework Statement

In a textbook it states:

-((4-x^2)^0.5) <= y <= ((4-x^2)^0.5)

And this is the same as being bounded by the circular region x^2 + y^2 <= 4

How do they conclude this?

Thank you.

Homework Equations

The Attempt at a Solution

 

[SammyS]

Homework Statement

In a textbook it states:

How do they conclude this?

Thank you.

Homework Equations

The Attempt at a Solution

If |u| ≤ a, where a is positive, then -a ≤ u ≤ a .

 

[ZedCar]

Thanks SammyS