Відповіді АЛГЕБРА: 20.24-25

20.24

x(t) = 5t – 23t³

1) t = 1c. 2) t = 3c.

U(t) = x‘(t) = 5 – 2t² U(3) = 5 – 2 • 3² = 5 – 18 = –13.

U(1) = 5 – 2 = 3 (м/с).

20.25

f’(x) = 0;

1) f(x) = cosx;–sinx = 0;x = πn, n є z.

2) f(x) = x2 – 6x;2x – 6 = 0;x = 3.