## iwanttogotostanford one year ago PLEASE HELP URGENT: For the function f(x) = 3(x − 1)2 + 2, identify the vertex, domain, and range.

1. iwanttogotostanford

@mathway @myininaya @CloverRacer @l

2. iwanttogotostanford

@shelby1290 @Bee_see @wolf1728

3. iwanttogotostanford

@vera_ewing

4. wolf1728

Would that be: f(x) = 3*(x − 1)*(x − 1) + 2 ?

5. iwanttogotostanford

yes

6. iwanttogotostanford

well it i this; f(x) = 3(x − 1)^2 + 2 sorry

The vertex form of a parabola is given as $$y = a (x-h)^2 + k$$ where the point $$(h,k)$$ is the vertex so comparing the two: $$y=3(x-1)^2 +2$$ and $$y=a(x-h)^2+k$$ can you tell me what you think the vertex is? :)

8. iwanttogotostanford

the first one?

9. wolf1728

Hmm, it seems sleepyhead is trying another approach, I multiplied it out: f(x) = 3*(x − 1)*(x − 1) + 2 equals 3 * x^2 -2x +1 +2 equals 3 x^2 -2x +3

I mean as a point :P or tell me h = k = that's ok too

yes, as it asks for the vertex - I assumed it would be easier to point it out since it is already in "vertex form" @wolf1728 :)

12. iwanttogotostanford

these are my choices: The vertex is (1, 2), the domain is all real numbers, and the range is y ≥ 2. The vertex is (1, 2), the domain is all real numbers, and the range is y ≤ 2. The vertex is (–1, 2), the domain is all real numbers, and the range is y ≥ 2. The vertex is (–1, 2), the domain is all real numbers, and the range is y ≤ 2.

then yes, your guess is correct! @iwanttogotostanford Good Job! :)

14. iwanttogotostanford

so it would be A?:_)

indeed ^_^

16. iwanttogotostanford

WAIT I HAVE ANOTHER QUSTION DONT LEAVE

17. iwanttogotostanford

18. iwanttogotostanford

Given the functions f(x) = 3x2, g(x) = x2 − 4x + 5, and h(x) = –2x2 + 4x + 1, rank them from least to greatest based on their axis of symmetry.

19. iwanttogotostanford

these are my choices:-) thanks for the help f(x), g(x), h(x) f(x), h(x), g(x) g(x), h(x), f(x) g(x), f(x), h(x)

the axis of symmetry is given by $$\large x = \frac{-b}{2a}$$ when the equations are in a form $$y=ax^2+bx+c$$

21. iwanttogotostanford

so it would be c? @sleepyhead314

yes :) that's what I got too! you're doing great ^_^

23. iwanttogotostanford

thank you! one more?? sorry.... @wolf1728 @sleepyhead314

24. iwanttogotostanford

Given the function f(x) = x2 and k = –1, which of the following represents a function opening downward? Answer choices: f(x) + k kf(x) f(x + k) f(kx)

perhaps consider making a new question so that we don't both wolf too much with the notifications :)

26. iwanttogotostanford

okay i will!

27. wolf1728

I made a mistake on previous problem f(x) = 3*(x − 1)*(x − 1) + 2 equals 3 * (x^2 -2x +1) +2 equals 3 x^2 -6x +5