а) f'(x) = 3х²-4х-7
б) 3х²-4х-7=0
t²-4t-21=0
t1= 7; 7÷3=7/3 => x1= 7/3 (л.к)
t2= -3; -3÷3 => x2= -1
f(-1) = -3-2+7-2 = -7+7=0
f(-4)= -64-2×16+28-2 = -64-32+28-2= -98+28= -70
f(2)= 8-2×4-14-2= 8-8-14-2= -16
ответ: f(-1) max = 0
f(-4) min = -70
а) f'(x) = 3х²-4х-7
б) 3х²-4х-7=0
t²-4t-21=0
t1= 7; 7÷3=7/3 => x1= 7/3 (л.к)
t2= -3; -3÷3 => x2= -1
f(-1) = -3-2+7-2 = -7+7=0
f(-4)= -64-2×16+28-2 = -64-32+28-2= -98+28= -70
f(2)= 8-2×4-14-2= 8-8-14-2= -16
ответ: f(-1) max = 0
f(-4) min = -70