Question

Given no other restrictions, what are the domain and range of the following function?

f(x)=x^2-2x+2

A. D= all real numbers
R={y|y>=1}

B. R=all real numbers
D={x|x>=1}

I think it is A...?

Answer 1

all polynomials have domain of all reals.
for the range, the vertex format is useful.

y = (x-1)^2 + 1
Since (x-1) is never less than zero,
y>=1
That's where the vertex is, at y=1.

So, (A) is the choice

Answer 2

thank u very much