y= 3x^3 - 16x + 2

a) increasing for x < -2.31 and x > 2.31; decreasing for -2.31 < x < 2.31

b) increasing for -2.31 < x < 2.31; decreasing for x < -2.31 and x > 2.31

c) increasing for x < - 4/3 and x > 4/3; decreasing for -4/3 < x < 4/3

d) increasing for -4/3 < 4/3; decreasing for x < -4/3 and x > 4/3

and what window did you use?