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Using the rational root theorem, list out all possible/candidate rational roots of $f(x)=2 x^{3}-28 x^{2}-5$. Express your answer as integers or as fractions in simplest form. Use commas to separate.
Answer Attempt 1 out of 2
Final Answer: The possible rational roots of the polynomial \(f(x)=2 x^{3}-28 x^{2}-5\) are \(\boxed{1, 5, \frac{1}{2}, -\frac{1}{2}, -5, \frac{5}{2}, -1, -\frac{5}{2}}\).
Step 1 :The Rational Root Theorem states that if a polynomial has a rational root, then it must be a factor of the constant term divided by a factor of the leading coefficient.
Step 2 :In this case, the constant term is -5 and the leading coefficient is 2.
Step 3 :So, we need to list out all the factors of -5 and 2, and form all possible fractions by dividing a factor of -5 by a factor of 2.
Step 4 :We also need to consider both positive and negative values, because a positive divided by a negative is a negative, and a negative divided by a positive is also a negative.
Step 5 :The factors of the constant term -5 are 1 and 5.
Step 6 :The factors of the leading coefficient 2 are 1 and 2.
Step 7 :By forming all possible fractions by dividing a factor of -5 by a factor of 2, we get the possible roots as 1, 5, \(\frac{1}{2}\), -\(\frac{1}{2}\), -5, \(\frac{5}{2}\), -1, -\(\frac{5}{2}\).
Step 8 :Final Answer: The possible rational roots of the polynomial \(f(x)=2 x^{3}-28 x^{2}-5\) are \(\boxed{1, 5, \frac{1}{2}, -\frac{1}{2}, -5, \frac{5}{2}, -1, -\frac{5}{2}}\).