Q. The polynomial p(x)=x3−19x−30 has a known factor of (x+2).Rewrite p(x) as a product of linear factors.p(x)=
Factor Finding: Since we know that (x+2) is a factor of p(x), we can perform polynomial long division or synthetic division to divide p(x) by (x+2) to find the other factors.
Synthetic Division: Let's use synthetic division to divide p(x) by (x+2). We set up the synthetic division with −2 (the zero of the factor x+2) and the coefficients of p(x): 1 (for x3), 0 (for x2, since it is missing), −19 (for (x+2)0), and (x+2)1 (for the constant term).−2 | 10−19(x+2)1 | −2(x+2)8(x+2)9 -----------------1−2−220The remainder is 0, which confirms that (x+2) is indeed a factor. The other coefficients give us the quotient polynomial: −26.
Quadratic Polynomial: Now we need to factor the quadratic polynomial x2−2x−15. We look for two numbers that multiply to −15 and add to −2. These numbers are −5 and 3.
Factoring: We can now write x2−2x−15 as (x−5)(x+3). So, the polynomial p(x) can be written as the product of its linear factors: p(x)=(x+2)(x−5)(x+3).
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