Solve, y" + 4y = tan(2t). solve using method of variation of parameters

If you are just building your payment history, how many points from a perfect score will you possibly miss?

Apinhole camera is made out of a light-tight box with a piece of film attached to one side and pinhole on the opposite side. the optimum diameter d(in millimeters) of the pinhole can be modeled by d=1.9[ (5.5 x 10^-4) l) ] ^1/2, where l is the length of the camera box (in millimeters). what is the optimum diameter for a pinhole camera if the camera box has a length of 10 centimeters

Secant be and cf intersect at point d inside a what is the measure of cde