Question

Постройте график функции f:R - R
в) f (x) = -2(x - 3)(5 - x)
е) f (x) = 4x(x - 2)

Answer 1

Ответ:

Разверните следующее:

f(x) = -2 (x - 3) (-x + 5)

(x - 3) (-x + 5) = (x) (5) + (x) (-x) + (-3) (5) + (-3) (-x) = 5 x - x^2 - 15 + 3 x = -x^2 + 8 x - 15:

f(x) = -2(-x^2 + 8 x - 15)

-2 (-x^2 + 8 x - 15) = -2 (-x^2) - 2 (8 x) - 2 (-15):

f(x) = (-2 (-1) x^2 - 2 8 x - 2 (-15))

-2 (-15) = 30:

f(x) = -2 (-1) x^2 - 2 8 x + 30

-2×8 = -16:

f(x) = -2 (-1) x^2 + -16 x + 30

-2 (-1) = 2:

Ответ: |

| f(x) = 2 x^2 - 16 x + 30