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Find all rational zeros of the polynomial, and write the polynomial in factored form.

P(x) = x³ – 4x² - 11x + 30

User MrKew
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1 Answer

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Final answer:

To find the rational zeros of the polynomial and write it in factored form, you can use the Rational Root Theorem. The possible rational zeros are 1, -1, 2, -2, 3, -3, 5, -5, 6, -6, 10, -10, 15, -15, 30, and -30. The factored form of the polynomial is (x-1)(x-6)(x+5).

Step-by-step explanation:

To find the rational zeros of the polynomial, we can use the Rational Root Theorem. The Rational Root Theorem states that if a rational number P/Q is a zero of a polynomial, where P is a factor of the constant term and Q is a factor of the leading coefficient, then P/Q will be a zero of the polynomial. In this case, the constant term is 30 and the leading coefficient is 1. The factors of 30 are ±1, ±2, ±3, ±5, ±6, ±10, ±15, ±30. Therefore, the possible rational zeros of the polynomial are:

  • x = 1/1
  • x = -1/1
  • x = 2/1
  • x = -2/1
  • x = 3/1
  • x = -3/1
  • x = 5/1
  • x = -5/1
  • x = 6/1
  • x = -6/1
  • x = 10/1
  • x = -10/1
  • x = 15/1
  • x = -15/1
  • x = 30/1
  • x = -30/1

To write the polynomial in factored form, we can use these zeros to factor the polynomial. We can start by using synthetic division to divide the polynomial by (x - 1), which gives us a quotient of x^2-3x-30. Then we can factor x^2-3x-30 using the quadratic formula or by using factoring techniques. The factored form of the polynomial is (x-1)(x-6)(x+5).

User Heartcroft
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