Question 408222: use the vertex formula to find the vertex
find the intervals where f is increasing and where f is decreasing
f(x)=2x^2-4x+1 Found 2 solutions by ewatrrr, MathLover1:Answer by ewatrrr(24785) (Show Source):
Hi
Using the vertex form of a parabola, where(h,k) is the vertex
f(x)= 2x^2-4x+1 |putting into the vertex form by completing the square
f(x)= 2[x^2-2] +1
f(x)= 2[(x - 1)^2 - 1] + 1
f(x)= 2(x - 1)^2 -2 + 1
f(x)= 2(x - 1)^2 -1 |vertex is Pt(1, -1)
f(x) is increasing from -1 to infinity
The vertex is found using the formula for (x,y):
(-b/2a,f(-b/2a))
find ...so we have (1,y)..now find ................ so the vertex is (1,-1)
the intervals on which the function is increasing and the intervals on which the function is decreasing
Given the vertex of (1,-1):
The function is decreasing on:
(-∞,1)
The function is increasing on:
(1,∞)
