How can I use the Rational Zeros Theorem to find all possible rational zeros of the function f(x) = 2x³ + 8x² – 7x – 8?

The Rational Zeros Theorem states that any rational solution, or zero, of a polynomial function can be expressed as a fraction p/q, where p is a factor of the constant term and q is a factor of the leading coefficient.

For the function f(x) = 2x³ + 8x² – 7x – 8, we first identify the constant term and the leading coefficient:

  • Constant term (the term without x): -8
  • Leading coefficient (the coefficient of x³): 2

Next, we find the factors of these terms:

Factors of -8:

  • 1, -1, 2, -2, 4, -4, 8, -8

Factors of 2:

  • 1, -1, 2, -2

Now, we can use these factors to list all possible rational zeros. By forming fractions p/q for all combinations of p (factors of -8) and q (factors of 2), we get:

  • 1/1, 1/2, -1/1, -1/2
  • 2/1, 2/2, -2/1, -2/2
  • 4/1, 4/2, -4/1, -4/2
  • 8/1, 8/2, -8/1, -8/2

Now, we simplify these fractions and combine like terms:

  • ±1, ±2, ±4, ±8
  • ±1/2

Combining all these gives us the complete list of the potential rational zeros:

Possible Rational Zeros:

  • 1, -1, 2, -2, 4, -4, 8, -8, 1/2, -1/2

Thus, using the Rational Zeros Theorem, we have determined that the possible rational zeros of the given function are ±1, ±2, ±4, ±8, ±1/2.

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