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Please help with this homework, so far I have asked 4 tudors

Please help with this homework, so far I have asked 4 tudors-example-1
User Windel
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1 Answer

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As we can see on the picture, the graphs crosses the x-axis at x=0 and it bounces of the x-axis at x=2. In the first case, the polynomial has a factor of degree 1 at x=0. In the second case, the factor has a degree 2 at x=2. So, we can write the following:


f(x)=A(x)(x-2)^2

where A is a constant to be determined. We can find this constant by noticing that when x=3, f(3)=3, then we have


3=A(3)(3-2)^2

which gives


\begin{gathered} 3=A\cdot3\cdot1^2 \\ 3=3A \\ \text{then} \\ A=1 \end{gathered}

Therefore, we get


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

Now, lets expand this result. By


\begin{gathered} f(x)=x(x^2-4x+4) \\ \end{gathered}

then, the answer is


f(x)=x^3-4x^2+4x

User BiXiC
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