Verify that the derivative of csc x is -csc x cot x. 

(Hint: Use the fact that csc x=1/sin x).

Solve the differential equation with the given initial condition (s).

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Find the area enclosed by the given ellipse.

Use the Chain Rule to find the indicated partial derivatives.

When, s=4, t=5, u=3

Differentiate each function with respect to x.