1. **Stating the problem:** Solve the equation $$x^2 + \frac{1}{x^2} = \frac{17}{4}$$ for $x$.
2. **Use a substitution to simplify:** Let $$y = x + \frac{1}{x}$$. We know the identity:
$$y^2 = \left(x + \frac{1}{x}\right)^2 = x^2 + 2 + \frac{1}{x^2}$$
which implies
$$x^2 + \frac{1}{x^2} = y^2 - 2$$
3. **Rewrite the original equation using $y$:**
$$y^2 - 2 = \frac{17}{4}$$
4. **Solve for $y^2$:**
$$y^2 = \frac{17}{4} + 2 = \frac{17}{4} + \frac{8}{4} = \frac{25}{4}$$
5. **Find $y$:**
$$y = \pm \frac{5}{2}$$
6. **Recall $y = x + \frac{1}{x}$, so solve for $x$:**
For $$y = \frac{5}{2}$$:
$$x + \frac{1}{x} = \frac{5}{2}$$
Multiply both sides by $x$:
$$x^2 + 1 = \frac{5}{2}x$$
Rearranged:
$$x^2 - \frac{5}{2}x + 1 = 0$$
7. **Solve quadratic equation:**
Use quadratic formula:
$$x = \frac{\frac{5}{2} \pm \sqrt{\left(\frac{5}{2}\right)^2 - 4 \cdot 1 \cdot 1}}{2} = \frac{\frac{5}{2} \pm \sqrt{\frac{25}{4} - 4}}{2} = \frac{\frac{5}{2} \pm \sqrt{\frac{25}{4} - \frac{16}{4}}}{2} = \frac{\frac{5}{2} \pm \sqrt{\frac{9}{4}}}{2}$$
Simplify the square root:
$$\sqrt{\frac{9}{4}} = \frac{3}{2}$$
So:
$$x = \frac{\frac{5}{2} \pm \frac{3}{2}}{2}$$
Calculate both solutions:
- $$x = \frac{\frac{5}{2} + \frac{3}{2}}{2} = \frac{\frac{8}{2}}{2} = \frac{4}{2} = 2$$
- $$x = \frac{\frac{5}{2} - \frac{3}{2}}{2} = \frac{\frac{2}{2}}{2} = \frac{1}{2}$$
8. **For $$y = -\frac{5}{2}$$:**
$$x + \frac{1}{x} = -\frac{5}{2}$$
Multiply both sides by $x$:
$$x^2 + 1 = -\frac{5}{2}x$$
Rearranged:
$$x^2 + \frac{5}{2}x + 1 = 0$$
9. **Solve quadratic:**
$$x = \frac{-\frac{5}{2} \pm \sqrt{\left(\frac{5}{2}\right)^2 - 4}}{2} = \frac{-\frac{5}{2} \pm \sqrt{\frac{25}{4} - 4}}{2} = \frac{-\frac{5}{2} \pm \frac{3}{2}}{2}$$
Calculate both solutions:
- $$x = \frac{-\frac{5}{2} + \frac{3}{2}}{2} = \frac{-\frac{2}{2}}{2} = \frac{-1}{2}$$
- $$x = \frac{-\frac{5}{2} - \frac{3}{2}}{2} = \frac{-\frac{8}{2}}{2} = \frac{-4}{2} = -2$$
10. **Final solutions:**
$$x = 2, \frac{1}{2}, -\frac{1}{2}, -2$$
These are the four values of $x$ satisfying the original equation.
Solve X Equation 1115Da
Step-by-step solutions with LaTeX - clean, fast, and student-friendly.