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# Find the Roots (Zeros) x^3-7x+6=0

Factor the left side of the equation.
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Factor using the rational roots test.
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If a polynomial function has integer coefficients, then every rational zero will have the form where is a factor of the constant and is a factor of the leading coefficient.
Find every combination of . These are the possible roots of the polynomial function.
Substitute and simplify the expression. In this case, the expression is equal to so is a root of the polynomial.
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Substitute into the polynomial.
Raise to the power of .
Multiply by .
Subtract from .
Since is a known root, divide the polynomial by to find the quotient polynomial. This polynomial can then be used to find the remaining roots.
Divide by .
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Set up the polynomials to be divided. If there is not a term for every exponent, insert one with a value of .
 - + - +
Divide the highest order term in the dividend by the highest order term in divisor .
 - + - +
Multiply the new quotient term by the divisor.
 - + - + + -
The expression needs to be subtracted from the dividend, so change all the signs in
 - + - + - +
After changing the signs, add the last dividend from the multiplied polynomial to find the new dividend.
 - + - + - + +
Pull the next terms from the original dividend down into the current dividend.
 - + - + - + + -
Divide the highest order term in the dividend by the highest order term in divisor .
 + - + - + - + + -
Multiply the new quotient term by the divisor.
 + - + - + - + + - + -
The expression needs to be subtracted from the dividend, so change all the signs in
 + - + - + - + + - - +
After changing the signs, add the last dividend from the multiplied polynomial to find the new dividend.
 + - + - + - + + - - + -
Pull the next terms from the original dividend down into the current dividend.
 + - + - + - + + - - + - +
Divide the highest order term in the dividend by the highest order term in divisor .
 + - - + - + - + + - - + - +
Multiply the new quotient term by the divisor.
 + - - + - + - + + - - + - + - +
The expression needs to be subtracted from the dividend, so change all the signs in
 + - - + - + - + + - - + - + + -
After changing the signs, add the last dividend from the multiplied polynomial to find the new dividend.
 + - - + - + - + + - - + - + + -
Since the remander is , the final answer is the quotient.
Write as a set of factors.
Factor using the AC method.
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Factor using the AC method.
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Consider the form . Find a pair of integers whose product is and whose sum is . In this case, whose product is and whose sum is .
Write the factored form using these integers.
Remove unnecessary parentheses.
If any individual factor on the left side of the equation is equal to , the entire expression will be equal to .
Set equal to and solve for .
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Set equal to .
Add to both sides of the equation.
Set equal to and solve for .
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Set equal to .
Add to both sides of the equation.
Set equal to and solve for .
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Set equal to .
Subtract from both sides of the equation.
The final solution is all the values that make true.