\( \int _{}^{}\frac{1}{(\frac{3x^{2}-1}{2})^{2}}e^{-\int _{}^{}\frac{2x}{1-x^{2}} d x} d x \)

3.- \( \quad f(x)=x \ln \cos x \)

Determine whether or not the vector field \( (x-46 x y) i+\left(y^{2}-23 x^{2}\right) j \) is conservative. If it is, find a potential function. \( f(x, y)=\frac{x^{2}}{2}-23 x^{2} y+y^{3}+c \). The field is not conservative. \( f(x, y)=x^{2}-23 x^{2} y+\frac{y^{3}}{3}+c \). The field is not conservative. \( f(x, y)=\frac{x^{2}}{2}-x^{2} y+\frac{y^{3}}{3}+c \). The field is conservative. \( f(x, y)=\frac{x^{2}}{2}-23 x^{2} y+\frac{y^{3}}{3}+c \). The field is conservative. \( f \)

52. \( \star \sum_{n=1}^{\infty} \sqrt{n}(\sin n)\left(\sin \frac{1}{n}\right)^{2} \)

Label each expression as a scalar quantity, a vector quantity or undefined, if \( f \) is a scalar function and \( F \) is a vector field. \( \nabla \times(\nabla f) \) scalar vector

Compute the work done by the force field \( F=\langle y, 0, z\rangle \) along the triangle from \( (0,0,0) \) to \( (2,3,4) \) then to \( (2,3,0) \) and then back to \( (0,0,0) \). \( W=\square \)