I need help to solve the problems.

Find all critical numbers and use the First Derivative Test to classify each as the location of a relative maximum, relative minimum or neither. You may use a chart or a number line to perform your sign tests. 5.) f( x) x 14x-2 6.) S(x) = x-2x*+2 7.) f (x) = - 8.) f (x) = Vx+3x2