Responder
To solve the inequality
\[
\frac{x(x+3)(x-3)+16}{(x+3)(x-2)} \geq -2,
\]
we first rearrange it to:
\[
\frac{x(x+3)(x-3)+16 + 2(x+3)(x-2)}{(x+3)(x-2)} \geq 0.
\]
Simplifying the numerator:
\[
x^3 + 2x^2 - 7x + 4 \geq 0.
\]
Factoring the numerator:
\[
(x - 1)^2(x + 4) \geq 0.
\]
The critical points are \(x = -4\), \(x = -3\), and \(x = 1\). Testing intervals:
- \(x < -4\): Negative
- \(-4 < x < -3\): Positive
- \(-3 < x < 1\): Positive
- \(x > 1\): Positive
Thus, the solution is:
\[
x \in (-4, -3) \cup (-3, 1] \cup (1, \infty).
\]
For the second inequality:
\[
\frac{2^{x}(2^{x}+3)(2^{x}-3)+16}{2^{2x}+2^{x}-6} \geq -2,
\]
let \(y = 2^x\), then:
\[
\frac{y(y+3)(y-3)+16}{y^2 + y - 6} \geq -2.
\]
Solving this inequality similarly will yield the solution for \(x\).
Solución
To solve the inequality
\[
\frac{x(x+3)(x-3)+16}{(x+3)(x-2)} \geq -2,
\]
we will first manipulate the inequality step by step.
### Step 1: Rearranging the Inequality
We start by moving \(-2\) to the left side:
\[
\frac{x(x+3)(x-3)+16}{(x+3)(x-2)} + 2 \geq 0.
\]
Next, we can express \(2\) with a common denominator:
\[
\frac{x(x+3)(x-3)+16 + 2(x+3)(x-2)}{(x+3)(x-2)} \geq 0.
\]
### Step 2: Simplifying the Numerator
Now, we need to simplify the numerator:
\[
x(x+3)(x-3) + 16 + 2(x+3)(x-2).
\]
Calculating \(2(x+3)(x-2)\):
\[
2(x+3)(x-2) = 2(x^2 + x - 6) = 2x^2 + 2x - 12.
\]
Now, we can expand \(x(x+3)(x-3)\):
\[
x(x^2 - 9) = x^3 - 9x.
\]
Combining everything, we have:
\[
x^3 - 9x + 16 + 2x^2 + 2x - 12 = x^3 + 2x^2 - 7x + 4.
\]
### Step 3: Final Inequality
Now we can rewrite the inequality:
\[
\frac{x^3 + 2x^2 - 7x + 4}{(x+3)(x-2)} \geq 0.
\]
### Step 4: Finding Roots of the Numerator
Next, we need to find the roots of the polynomial \(x^3 + 2x^2 - 7x + 4\). We can use the Rational Root Theorem to test possible rational roots. Testing \(x = 1\):
\[
1^3 + 2(1^2) - 7(1) + 4 = 1 + 2 - 7 + 4 = 0.
\]
Thus, \(x = 1\) is a root. We can factor the polynomial using synthetic division:
\[
x^3 + 2x^2 - 7x + 4 = (x - 1)(x^2 + 3x - 4).
\]
Now we can factor \(x^2 + 3x - 4\):
\[
x^2 + 3x - 4 = (x + 4)(x - 1).
\]
Thus, the complete factorization is:
\[
(x - 1)^2(x + 4).
\]
### Step 5: Analyzing the Inequality
Now we have:
\[
\frac{(x - 1)^2(x + 4)}{(x + 3)(x - 2)} \geq 0.
\]
The critical points are \(x = -4\), \(x = -3\), \(x = 1\), and \(x = 2\). We will test intervals around these points:
1. **Interval \((- \infty, -4)\)**: Choose \(x = -5\):
\[
\frac{(-5 - 1)^2(-5 + 4)}{(-5 + 3)(-5 - 2)} = \frac{36(-1)}{(-2)(-7)} < 0.
\]
2. **Interval \((-4, -3)\)**: Choose \(x = -3.5\):
\[
\frac{(-3.5 - 1)^2(-3.5 + 4)}{(-3.5 + 3)(-3.5 - 2)} > 0.
\]
3. **Interval \((-3, 1)\)**: Choose \(x = 0\):
\[
\frac{(0 - 1)^2(0 + 4)}{(0 + 3)(0 - 2)} > 0.
\]
4. **Interval \((1, 2)\)**: Choose \(x = 1.5\):
\[
\frac{(1.5 - 1)^2(1.5 + 4)}{(1.5 + 3)(1.5 - 2)} < 0.
\]
5. **Interval \((2, \infty)\)**: Choose \(x = 3\):
\[
\frac{(3 - 1)^2(3 + 4)}{(3 + 3)(3 - 2)} > 0.
\]
### Step 6: Conclusion for the First Inequality
The solution to the inequality is:
\[
(-4, -3) \cup (-3, 1] \cup (2, \infty).
\]
### Step 7: Solving the Second Inequality
Now we need to solve the inequality
\[
\frac{2^{x}(2^{x}+3)(2^{x}-3)+16}{2^{2x}+2^{x}-6} \geq -2.
\]
Let \(y = 2^x\
Revisado y aprobado por el equipo de tutoría de UpStudy
Explicar
Simplifique esta solución