y = 5x^2-20x-1, x ∈ [1;3]
max y - ?
y' = 10x-20
y' = 0
10x-20 = 0
10x = 20
x = 2 — критическая точка
ответ: max y(1) = -16 и max y(3) = -16; x ∈ [1;3].
y = 5x^2-20x-1, x ∈ [1;3]
max y - ?
y' = 10x-20
y' = 0
10x-20 = 0
10x = 20
x = 2 — критическая точка
y(2) = 5·2^2-20·2-1 = 20-40-1 = -21y(1) = 5·1^2-20·1-1 = 5-20-1 = -16y(3) = 5·3^2-20·3-1 = 45-60-1 = -16ответ: max y(1) = -16 и max y(3) = -16; x ∈ [1;3].