Questions: Use Green's Theorem to evaluate the line integral. Assume the curve is oriented counterclockwise.
∮(2x+sinh y) dy-(5y^2+e^(x^2)) dx, where C is the boundary of the square with vertices (1,3),(3,3),(3,5), and (1,5).
∮(2x+sinh y) dy-(5y^2+e^(x^2)) dx=
(Type an exact answer.)
Transcript text: Use Green's Theorem to evaluate the line integral. Assume the curve is oriented counterclockwise.
$\oint_{C}(2 x+\sinh y) d y-\left(5 y^{2}+e^{x^{2}}\right) d x$, where $C$ is the boundary of the square with vertices $(1,3),(3,3),(3,5)$, and $(1,5)$.
\[
\oint_{C}(2 x+\sinh y) d y-\left(5 y^{2}+e^{x^{2}}\right) d x=
\]
(Type an exact answer.)
Solution
Solution Steps
To evaluate the line integral using Green's Theorem, we need to convert the line integral over the closed curve \( C \) into a double integral over the region \( R \) enclosed by \( C \). Green's Theorem states that for a vector field \(\mathbf{F} = (M, N)\), the line integral \(\oint_C M \, dx + N \, dy\) is equal to the double integral \(\iint_R \left( \frac{\partial N}{\partial x} - \frac{\partial M}{\partial y} \right) \, dA\). Here, \( M = -(5y^2 + e^{x^2}) \) and \( N = 2x + \sinh y \). We will compute the partial derivatives, set up the double integral over the square region, and evaluate it.
Step 1: Define the Vector Field
We start with the vector field defined by the line integral:
\[
\oint_{C} (2x + \sinh y) \, dy - (5y^2 + e^{x^2}) \, dx
\]
Here, we identify \( M = -(5y^2 + e^{x^2}) \) and \( N = 2x + \sinh y \).
Step 2: Compute the Partial Derivatives
Next, we compute the partial derivatives:
\[
\frac{\partial N}{\partial x} = 2
\]
\[
\frac{\partial M}{\partial y} = -10y
\]
Step 3: Set Up the Integrand
Using Green's Theorem, we find the integrand for the double integral:
\[
\frac{\partial N}{\partial x} - \frac{\partial M}{\partial y} = 2 + 10y
\]
Step 4: Define the Region of Integration
The region \( R \) is defined by the square with vertices \((1,3)\), \((3,3)\), \((3,5)\), and \((1,5)\). The limits of integration are:
\[
x \text{ from } 1 \text{ to } 3, \quad y \text{ from } 3 \text{ to } 5
\]
Step 5: Evaluate the Double Integral
We evaluate the double integral:
\[
\iint_R (2 + 10y) \, dA = \int_{1}^{3} \int_{3}^{5} (2 + 10y) \, dy \, dx
\]
Calculating this integral gives us the result:
\[
\text{Result} = 168
\]
Final Answer
Thus, the value of the line integral is:
\[
\boxed{168}
\]