1. Find the function f g and its domain if f(x)= sqroot x+10 and g(x)= sqroot x-10?

2. The point P(1,8) lies on the curve y=8/x² . Find an equation of the tangent line to the curve at P(1,8)?

3. A television camera is positioned 4,600 ft from the base of a rocket launching pad. The angle of elevation of the camera has to change at the correct rate in order to keep the rocket in sight. Also, the mechanism for focusing the camera has to take into account the increasing distance from the camera to the rising rocket. Let's assume the rocket rises vertically and its speed is 680 ft/s when it has risen 2,600 ft. If the television camera is always kept aimed at the rocket, how fast is the camera's angle of elevation changing at this moment? Do not round any values in your calculation.