Log Inverse 7Dd253
1. **Problem:** Find the inverse of the logarithmic function $$y = \log_5(2x - 1) - 7$$.
2. **Recall the definition of inverse functions:** If $$y = f(x)$$, then the inverse function $$x = f^{-1}(y)$$ satisfies $$f(f^{-1}(y)) = y$$ and $$f^{-1}(f(x)) = x$$.
3. **Step to find the inverse:** Swap $$x$$ and $$y$$ and solve for $$y$$.
Start with:
$$y = \log_5(2x - 1) - 7$$
Swap $$x$$ and $$y$$:
$$x = \log_5(2y - 1) - 7$$
4. **Isolate the logarithm:**
$$x + 7 = \log_5(2y - 1)$$
5. **Rewrite the logarithmic equation in exponential form:**
$$5^{x + 7} = 2y - 1$$
6. **Solve for $$y$$:**
$$2y = 5^{x + 7} + 1$$
$$y = \frac{5^{x + 7} + 1}{2}$$
7. **Therefore, the inverse function is:**
$$f^{-1}(x) = \frac{5^{x + 7} + 1}{2}$$
---
**Desmos graph for the original function:**
$$y = \log_5(2x - 1) - 7$$
**Features:** intercepts and extrema are not typical for logarithmic functions shifted this way, but intercepts can be checked.
---
"slug": "log inverse",
"subject": "calculus",
"desmos": {
"latex": "y=\log_5(2x-1)-7",
"features": {
"intercepts": true,
"extrema": true
}
},
"q_count": 2