Q. The polynomial p(x)=x3−7x−6 has a known factor of (x+1).Rewrite p(x) as a product of linear factors.p(x)=
Factor Finding Method: Since we know that (x+1) is a factor of p(x), we can perform polynomial division or use synthetic division to divide p(x) by (x+1) to find the other factors.
Synthetic Division Setup: Let's use synthetic division to divide p(x) by (x+1). We set up the synthetic division with −1 (the zero of the factor x+1) and the coefficients of p(x): 1 (for x3), 0 (for x2, since there is no x2 term), (x+1)0 (for (x+1)1), and (x+1)2 (constant term).
Performing Synthetic Division: Performing synthetic division, we bring down the leading 1, multiply it by −1 to get −1, add this to the next coefficient (0) to get −1, multiply −1 by −1 to get 1, add this to −7 to get −6, multiply −6 by −1 to get −12, and add this to −6 to get −14. The result of the synthetic division is the coefficients of the quotient polynomial: 1 (for −16), −1 (for −18), and −6 (for the constant term).
Quotient Polynomial: The quotient polynomial is x2−x−6. We can factor this quadratic polynomial to find the other linear factors of p(x).
Factoring Quadratic Polynomial: Factoring x2−x−6, we look for two numbers that multiply to −6 and add to −1. These numbers are −3 and 2. Therefore, x2−x−6 factors into (x−3)(x+2).
Final Solution: Now we can write p(x) as a product of its linear factors: p(x)=(x+1)(x−3)(x+2).
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