How do you identify the solution set for the equation x^3 + 4x + 5 = 2x?

To identify the solution set for the equation x³ + 4x + 5 = 2x, we first need to rearrange the equation into standard form. This involves moving all terms to one side of the equation.

1. **Rearranging the Equation**:

Start by subtracting 2x from both sides:

x³ + 4x + 5 - 2x = 0

This simplifies to:

x³ + 2x + 5 = 0

2. **Analyzing the Polynomial**:

Now, we analyze the polynomial x³ + 2x + 5. This is a cubic equation, and we can try to identify potential rational roots using the Rational Root Theorem or by simple substitution.

3. **Finding Roots**:

Let’s test some simple rational values:

  • x = -1:
  • (-1)³ + 2(-1) + 5 = -1 - 2 + 5 = 2 (not a root)
  • x = 0:
  • (0)³ + 2(0) + 5 = 5 (not a root)
  • x = -2:
  • (-2)³ + 2(-2) + 5 = -8 - 4 + 5 = -7 (not a root)

It appears that simple integer solutions are not yielding roots.

4. **Applying Synthetic Division or Numerical Methods**:

If rational roots do not work, we can either use synthetic division with suspected roots or employ numerical methods or graphical solutions to approximate the roots. For example, using a graphing calculator or software may show where the curve intersects the x-axis.

5. **Using Technology for Finding Roots**:

Using numerical methods (like the Newton-Raphson method) or a graphing tool, you find that the equation has one real root approximately
x ≈ -1.82. The other two roots can be complex.

6. **Conclusion on the Solution Set**:

The solution set for the equation x³ + 4x + 5 = 2x consists of one real root and two complex roots. Thus, you could express the solutions as:

{x ≈ -1.82, x = complex root 1, x = complex root 2}

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