The function $f(x)$ is defined only on domain $[-1,2]$, and is defined on this domain by the formula f(x)=2x2−8x+1. What is the range of $f(x)$? Express your answer as an interval or as a union of intervals.
The x coordinate of the vertex is 8 / (2*2) = 2
f(-1) = 2(-1)^2 - 8(-1) + 1 = 11
f(2) = 2(2)^2 - 8(2) + 1 = -7
The vertex is (2,-7)
So....the range on [-1,2] is [ -7, 11]
+921 
