need help please

Find the critical numbers of the function 1 ) f( 20 ) = 2 3 + 2 2 - x 2 ) f ( x ) = 2 3 + x 2 + x 3 ) s ( t ) = 3t" + 4 + 3 - 6t 2 Find the absolute maximum and absolute minimum values of f on the given interval 1 ) f (c ) = 3 2 2 - 12 x * + 5 [0 3] 2 ) f(x ) = 23 - box 2 + 9 x + 2 El , 4 ] 3) f (c ) = x [ 0 , 3 ] 2 + 4