What is the domain and range of y+2 = (x-3)^2?

1 Answer
Jun 14, 2018

Domain: x inRR
Range: y in [-2,oo)

Explanation:

The function you provided is almost in vertex form of a quadratic function, which helps greatly when answering your question. Vertex form in a quadratic is when the function is written in the following form:

y=a(x-h)^2+k

To write your function in vertex form, I'll simply solve for y by subtracting 2 from both sides:

y=(x-3)^2-2

The two parameters you want in this are a and k, since those will actually tell you the range. Since any value of x can be used in this function, the domain is:

x inRR

Now we need the range. As stated before, it comes from the values of a and k. If a is negative, the range goes to-oo. If a is positive, the range goes to oo. In this case, a is positive, so we know the range goes to oo. The lowest value will be the k value, which in this case is -2. Hence, the range of your function is:

y in [-2,oo)