Which is a rational function? a. y=x-5/2 b. y=x-3/x^2 c. y=x-3/x^2 d. y=2^x

Question

Which is a rational function? a. y=x-5/2  b. y=x-3/x^2  c. y=x-3/x^2  d. y=2^x

mathmale · Answer

What is a rational function, anyway?
A rational function is the ratio of two polynomials.
What is a polynomial?

Why not start by eliminating the obviously wrong answers?  (d) is one such answer.  It's not made up of one polynomial divided by another polynomial.

Please note:  Your (b) and your (c) appear to be identical.  Mind going back to check what (b) and (c) are in the original problem?

anonymous · Answer

b. y=x^2-x+4 sorry

mathmale · Answer

So, of these four functions, which ones could be eliminated as possible answers?
Again, a rational function is the ratio of two polynomials.  What is a polynomial?

anonymous · Answer

b and d can be eliminated?