Відповіді АЛГЕБРА: 22.7

22.7

1) f(x) = 2x – 7;

f’(x) = 2 ≠ 0 екстремумів нема;

2) f(x) = 2x² – 4x + 5;

f’(x) = 4x – 4;

4x – 4 = 0;

x = 1;

Xmin = 1;

ymin = 2 – 4 + 5 = 3;

3) f(x) = 6 – 12x – x2;

f‘(x) = –12 – 2x;

–12 – 2x = 0;

2x = –12;

x = –6;

Xmax = –6;

ymax = 6 + 72 – 36 = 42.

4) f(x) = 3x² – x³

f’(x) = 6x – 3x²

6x – 3x² = 0;

3x(2 – x) = 0;

x = 0; x = 2;

Xmin = 0; ymin = 0;

Xmax = 2; ymax = 3 • 4 – 8 = 12 – 8 = 4 .