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I tried to answer it but it says its wrong

I tried to answer it but it says its wrong-example-1
User Chao Ruan
by
5.7k points

1 Answer

3 votes

We have


f(x)=(1)/(2)(x-1)^2-2

This is a parabola in the vertex form, we can see that the vertex of the parabola is


(1,-2)

Because of the vertex form:


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

There the vertex is


(h,k)

Then, we can already plot one point of the parabola


(1,-2)

Let's also find the y-intercept, doing x = 0


\begin{gathered} f(x)=(1)/(2)(x-1)^(2)-2 \\ \\ f(0)=(1)/(2)(0-1)^2-2 \\ \\ f(0)=(1)/(2)(-1)^2-2 \\ \\ f(0)=(1)/(2)-2 \\ \\ f(0)=-(3)/(2) \end{gathered}

Therefore we have another point


(0,-3/2)

We can also find the zeros of that parabola doing y = 0


\begin{gathered} 0=(1)/(2)(x-1)^2-2 \\ \\ (1)/(2)(x-1)^2=2 \\ \\ (x-1)^2=4 \\ \\ (x-1)^2=4=\begin{cases}x-1={2} \\ x-1=-2\end{cases} \\ \\ \end{gathered}

Solving the two linear equations we get the zeros


\begin{gathered} x-1=2\Rightarrow x=3 \\ x-1=-2\operatorname{\Rightarrow}x=-1 \end{gathered}

The zeros are 3 and -1. We have all the points to draw a perfect parabola!

Draw the parabola

I tried to answer it but it says its wrong-example-1
I tried to answer it but it says its wrong-example-2
User Daniel Gruszczyk
by
5.1k points
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