Questions: Differentiate implicitly to find dy/dx. Then find the slope of the curve at the given point.
6x^2 - 7y^3 = -394 ; (-3,4)
dy/dx =
Transcript text: Differentiate implicitly to find $\frac{d y}{d x}$. Then find the slope of the curve at the given point.
\[
\begin{array}{l}
6 x^{2}-7 y^{3}=-394 ; \quad(-3,4) \\
\frac{d y}{d x}=\square
\end{array}
\]
$\square$
Solution
Solution Steps
To find \(\frac{dy}{dx}\) using implicit differentiation, differentiate both sides of the equation with respect to \(x\), applying the chain rule to terms involving \(y\). Then, solve for \(\frac{dy}{dx}\). To find the slope at the given point \((-3, 4)\), substitute \(x = -3\) and \(y = 4\) into the expression for \(\frac{dy}{dx}\).
Step 1: Implicit Differentiation
We start with the equation given by \( 6x^2 - 7y^3 = -394 \). To find \(\frac{dy}{dx}\), we differentiate both sides with respect to \(x\):
\[
\frac{d}{dx}(6x^2) - \frac{d}{dx}(7y^3) = 0
\]
This results in:
\[
12x - 21y^2 \frac{dy}{dx} = 0
\]
Step 2: Solve for \(\frac{dy}{dx}\)
Rearranging the equation gives us:
\[
21y^2 \frac{dy}{dx} = 12x
\]
Thus, we can express \(\frac{dy}{dx}\) as:
\[
\frac{dy}{dx} = \frac{12x}{21y^2} = \frac{4x}{7y^2}
\]
Step 3: Evaluate the Slope at the Given Point
Next, we substitute the point \((-3, 4)\) into the expression for \(\frac{dy}{dx}\):
\[
\frac{dy}{dx} \bigg|_{(-3, 4)} = \frac{4(-3)}{7(4^2)} = \frac{-12}{7 \cdot 16} = \frac{-12}{112} = \frac{-3}{28}
\]
Final Answer
The slope of the curve at the point \((-3, 4)\) is \(\boxed{\frac{-3}{28}}\).