Roots Synthetic 349461
1. **State the problem:** Find the roots of the polynomial equation $$4x^3 + 7x^2 - 5x - 6 = 0$$ using synthetic division.
2. **Recall the Rational Root Theorem:** Possible rational roots are factors of the constant term divided by factors of the leading coefficient. Here, constant term = -6, leading coefficient = 4.
3. **Possible roots:** $$\pm 1, \pm 2, \pm 3, \pm 6, \pm \frac{1}{2}, \pm \frac{3}{2}, \pm \frac{1}{4}, \pm \frac{3}{4}$$
4. **Test roots using synthetic division:** Start with $x=1$.
Synthetic division setup for $x=1$:
Coefficients: 4 | 7 | -5 | -6
Bring down 4.
Multiply 4*1=4, add to 7 = 11.
Multiply 11*1=11, add to -5 = 6.
Multiply 6*1=6, add to -6 = 0.
Remainder is 0, so $x=1$ is a root.
5. **Divide polynomial by $(x-1)$:** Quotient polynomial is $$4x^2 + 11x + 6$$
6. **Factor the quadratic:**
$$4x^2 + 11x + 6 = (4x + 3)(x + 2)$$
7. **Find roots of factors:**
$$4x + 3 = 0 \Rightarrow x = -\frac{3}{4}$$
$$x + 2 = 0 \Rightarrow x = -2$$
8. **Final roots:** $$x = 1, -\frac{3}{4}, -2$$
This completes the solution for the first polynomial.