1. **Problem Statement:**
We need to find the invariant points of the reciprocal of a linear function. An invariant point is where the function and its reciprocal intersect, meaning the point satisfies $f(x) = \frac{1}{f(x)}$.
2. **Formula and Explanation:**
For a linear function $f(x) = mx + b$, the reciprocal function is $y = \frac{1}{mx + b}$.
An invariant point satisfies:
$$
f(x) = \frac{1}{f(x)}
$$
which implies
$$
mx + b = \frac{1}{mx + b}
$$
3. **Solve for invariant points:**
Multiply both sides by $mx + b$:
$$
(mx + b)(mx + b) = 1
$$
which is
$$
(mx + b)^2 = 1
$$
4. **Expand and simplify:**
$$
(m^2 x^2 + 2mbx + b^2) = 1
$$
5. **Rewrite as a quadratic equation:**
$$
m^2 x^2 + 2mb x + (b^2 - 1) = 0
$$
6. **Use the quadratic formula:**
$$
x = \frac{-2mb \pm \sqrt{(2mb)^2 - 4 m^2 (b^2 - 1)}}{2 m^2}
$$
Simplify inside the square root:
$$
(2mb)^2 - 4 m^2 (b^2 - 1) = 4 m^2 b^2 - 4 m^2 b^2 + 4 m^2 = 4 m^2
$$
So,
$$
x = \frac{-2mb \pm 2m}{2 m^2} = \frac{-mb \pm m}{m^2} = \frac{m(-b \pm 1)}{m^2} = \frac{-b \pm 1}{m}
$$
7. **Final invariant points:**
$$
\left(\frac{-b + 1}{m}, 1 - b\right) \quad \text{and} \quad \left(\frac{-b - 1}{m}, -1 - b\right)
$$
where the $y$-values come from substituting $x$ back into $f(x) = mx + b$.
**Summary:**
The reciprocal of a linear function $f(x) = mx + b$ has two invariant points at
$$
\left(\frac{-b + 1}{m}, 1 - b\right) \quad \text{and} \quad \left(\frac{-b - 1}{m}, -1 - b\right)
$$
These points lie on both the function and its reciprocal.
This explains why different answers occur: the invariant points depend on the slope $m$ and intercept $b$ of the original linear function.
q_count is 2 because the user asked about the reciprocal function sketch and invariant points, but we only solve the invariant points as per instructions.
Invariant Points Bbee29
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