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Write a polynomial function of least degree with the given zeros: -2, 1,4

User Harry Pehkonen
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1 Answer

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Since we want a polynomial p(x) with zeros -2,1 and 4, we have the following expression:


p(x)=(x-(-2))(x-1)(x-4)

If we multiply these factors we get:


\begin{gathered} p(x)=(x+2)(x-1)(x-4) \\ \Rightarrow p(x)=(x^2+x-2)(x-4) \\ \Rightarrow p(x)=x^3-4x^2+x^2-4x-2x+8 \\ p(x)=x^3-3x^2-6x+8 \end{gathered}

Therefore, the polynomial function with the given zeros is p(x)=x^3-3x^2-6x+8

User Montrealist
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