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Please help. It’s algebra 2

Please help. It’s algebra 2-example-1
User Tulani
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The polynomial function of least degree with rational coefficients, a leading coefficient of 1, and the given value of 4.6 - √7 is:


f(x) = x^2 - 7 (in standard form)

How to create a polynomial function

To create a polynomial function of least degree with rational coefficients, a leading coefficient of 1, and the given value of 4.6 - √7, use the concept of conjugate pairs.

The conjugate of √7 is -√7.

The conjugate pairs allow us to eliminate the irrational part (√7) by utilizing the difference of squares. The product of a conjugate pair results in a rational expression.

Let's denote x as the irrational part (√7) and create the polynomial function:


f(x) = (x - (\sqrt7))(x - (-\sqrt7))

Expanding the expression:


f(x) = (x - \sqrt7)(x + \sqrt7)\\f(x) = x^2 - \sqrt7x + \sqrt7x - (\sqrt7)(-\sqrt7)\\f(x) = x^2 - (\sqrt7)(-\sqrt7)\\f(x) = x^2 - 7

Therefore, the polynomial function of least degree with rational coefficients, a leading coefficient of 1, and the given value of 4.6 - √7 is:


f(x) = x^2 - 7 (in standard form)

User Cvogt
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