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How do you find the zero’s algebraically?

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To find the zeros of a polynomial algebraically, you can use the following steps:

Write the polynomial in standard form, with the terms arranged in descending order of the degree of the term. For example, if the polynomial is 3x^2 - 2x + 5, it is already in standard form.

Set the polynomial equal to zero. For example, if the polynomial is 3x^2 - 2x + 5, you would set the equation equal to zero like this:

3x^2 - 2x + 5 = 0

Use the quadratic formula to find the solutions (i.e., the zeros) of the equation if the polynomial is a quadratic (degree 2). The quadratic formula is:

x = (-b +/- sqrt(b^2 - 4ac)) / (2a)

where a, b, and c are the coefficients of the polynomial, and sqrt represents the square root.

For example, if the polynomial is 3x^2 - 2x + 5, the solutions would be:

x = (-(-2) +/- sqrt((-2)^2 - 4 * 3 * 5)) / (2 * 3)

x = (2 +/- sqrt(4 - 60)) / 6

x = (2 +/- sqrt(-56)) / 6

Since the square root of a negative number is not a real number, there are no real solutions (zeros) for this polynomial.

Use the Rational Root Theorem to find the solutions of the equation if the polynomial is not a quadratic. The Rational Root Theorem states that if a polynomial of degree n has a rational root p/q (where p and q are integers and q is not equal to zero), then p must be a divisor of the constant term and q must be a divisor of the coefficient of the term of highest degree.

For example, if the polynomial is x^3 - 2x^2 + x - 6, the constant term is -6 and the coefficient of the term of highest degree is 1. The divisors of -6 are -6, -3, -2, -1, 1, 2, 3, and 6. The divisors of 1 are 1 and -1. Therefore, the possible rational roots of this polynomial are -6, -3, -2, -1, 1, 2, 3, and 6.

To find the actual roots, you can try each of these numbers as a root and see if it works. For example, if you try -6 as a root, you would get:

(-6)^3 - 2(-6)^2 + (-6) - 6 = 0

(-216) - (-72) + (-6) - 6 = 0

-144 - 6 - 6 = 0

-156 = 0

This equation is not true, so -6 is not a root of the polynomial. You can repeat this process for each of the other possible rational roots until you find all of the roots of the polynomial.

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