1)y`=3x²+2x-8=0
D=4+96=100
x1=(-2-10)/6=-2
x2=(-2+10)/6=4/3
+ _ +
----------------------------------------
-2 4/3
max
2)y`=3x²-8x-3=0
D=64+36=100
x1=(8-10)/6=-1/3
x2=(8+10)/6=3
+ _ +
----------------------------------------
-1/3 3
min
3)y`=3x²+16x+16=0
D=256-192=64
x1=(-16-8)/6=-4
x2=(-16+8)/6=-4/3
+ _ +
----------------------------------------
-4 -4/3
max