Problem (2) (6 points) Using the (limit) definition of derivative to show that the derivative of the function sin(x) is cos(x), i.e., & sin(x) = cos(x) . [Hint: sin(a + 3) = sin a cos B + cos a sin B. cos(a + B) = cosa cos B - sin a sin B . Problem(3) (5 points) Using the quotient rule of derivative to show that the derivative of the function cot(x) is - csc?(x), i.e., da cot(x) = - csc2(x)