How do you decide whether the relation 2x^2+7y^2=1 defines a function?

1 Answer
salamat
Mar 30, 2017

not a function

Explanation:

2 x^2 + 7 y^2 = 1
7y^2 = 1 - 2 x^2
y^2 = (1 - 2 x^2)/7
y = +- sqrt((1 - 2 x^2)/7)

it is not a function because one value of x has more than one value of y. It means one domain has more than one codomain. Function must has one-to-one or more-to-one relations only.

Related questions
See all questions in Functions on a Cartesian Plane
Impact of this question
2489 views around the world
You can reuse this answer
Creative Commons License