SOLUTION: f(x)=1/2(x+1)^2-3 how i find the points (x,y) in order to graph this parabola?

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Question 769251: f(x)=1/2(x+1)^2-3
how i find the points (x,y) in order to graph this parabola?

Found 2 solutions by josgarithmetic, lwsshak3:
Answer by josgarithmetic(39621) About Me  (Show Source):
You can put this solution on YOUR website!
You mean this: f%28x%29=%281%2F2%29%28x%2B1%29%5E2-3

The function is in standard form allowing you to read the vertex and understand from lead coefficient greater than zero, vertex is a minimum. The vertex is at (-1,-3), and parabola opens upward. Setting x=0, y intercept is 1%2F2-3=-2%261%2F2, or the point, (0,-5/2).

Also, being in standard form makes find x intercepts fairly easy, because setting f(x)=0, just so few steps needed to solve for x.
3=%281%2F2%29%28x%2B1%29%5E2
6=%28x%2B1%29%5E2
x%2B1=0%2B-sqrt%286%29
highlight%28x=-1%2B-sqrt%286%29%29, and sqrt(6) is near 2.45.




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Note that the reason for 0%2B-sqrt%286%29 showing the zero is so that the rendering would work and the expression, equation be more easily read.

Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
f(x)=
how i find the points (x,y) in order to graph this parabola?
This is an equation of a parabola that opens upwards.(lead coefficient>0)
Its standard form: y=A(x-h)^2+k, (h,k)=(x,y) coordinates of the vertex. A is a coefficient that affects the slope or narrowness of the curve.
With given equation, you have coordinates of the vertex (-1,-3)
Next, find the x-intercepts.
set y=0
1/2(x+1)^2-3=0
1/2(x+1)^2=3
(x+1)^2=6
(x+1)=±√6
x=-1±√6=-1±2.45
x=-3.45 and 1.45
You can now draw graph of given parabola with coordinates of the vertex, the x-intercepts, and knowing that the parabola opens upward.