1. **Problem statement:** Find the derivative $\frac{dy}{dx}$ and the exact coordinates of point B. 2. **Step 1: Identify the function and point B.** Since the function or coordinates of B are not given, please provide the function $y=f(x)$ and the location or definition of point B. 3. **Step 2: Formula for derivative.** The derivative $\frac{dy}{dx}$ of a function $y=f(x)$ is given by: $$\frac{dy}{dx} = \lim_{h \to 0} \frac{f(x+h) - f(x)}{h}$$ This represents the slope of the tangent line to the curve at any point $x$. 4. **Step 3: Finding coordinates of B.** Usually, point B is defined by a specific $x$-value or condition on the function. Once the function is known, substitute the $x$-value into $y=f(x)$ to find the exact coordinates $(x_B, y_B)$. 5. **Step 4: Calculate $\frac{dy}{dx}$ at point B.** After finding $x_B$, compute $\frac{dy}{dx}$ at $x=x_B$ to get the slope of the tangent at B. Please provide the function and any details about point B to proceed with exact calculations.