Math Is Fun Forum

mathxyz

Member

From: Brooklyn, NY

Registered: 2024-02-24

Posts: 1,053

Is y a Function of x?

Determine if each equation defines y as a function of x.

1. y = x^3

I say yes.

2. y = | x |

I say yes.

3. y = ± sqrt{1 - 2x}

I say yes.

Do you agree? If not, why not?

amnkb

Member

Registered: 2023-09-19

Posts: 253

Re: Is y a Function of x?

1. agree

2. agree

3. no: plus-minus means every x gives 2 y's.

mathxyz

Member

From: Brooklyn, NY

Registered: 2024-02-24

Posts: 1,053

Re: Is y a Function of x?

1. agree

2. agree

3. no: plus-minus means every x gives 2 y's.

I had a feeling that number 3 is not a function but didn't know the reason why.