Find the points of inflection. 1) f(x)=7x3+2x+4 A) (0,4) 2) f(x) = x4 - 2x3 + 12 A) (2,0) 1) B) (0, 2) C) (4,0) D) (2,0) 2) B) (2,4) C) (0, 12), (2, -8) D) (0, 12), (2,4) 3) f(x) = x-12x + 2x + 15 A) (4,-252) B) (4,-46) C) (4,-105) Determine where the given function is concave up and where it is concave down. 4) f(x)=4x-x3 A) Concave up on (-0, 0), concave down on (0, ) B) Concave down for all t C) Concave up on (0, ), concave down on (-, 0) D) Concave up on (-0, 0) and (1, ), concave down on (0, 1) 3) D) (-4, -48) 4) 6) f(x)=x36-x2 A) Concave down on (-6, 0), concave up on (0, 6) B) Concave up on (-, 0), concave down on (0, 0) C) Concave up on (-,) D) Concave up on (-6, 0), concave down on (0, 6) 6)