18) f '(x) = (-2)' * ctgx - (-2)* (ctgx)' = 0 * ctgx + 2 * (- 1/Sin²x) = - 2/Sin²x
19) f ' (x) = (Sin15x)' = Cos15x * (15x)' = 15Cos15x
20) f '(x) = [Cos(π/4 - 12x)] ' = - Sin(π/4 - 12x) * (π/4 - 12x)' = 12Sin(π/4 - 12x)
Не знаю прости сам подумай
Ответ:
0,1⁴ × 90000+ 1/9² × 27 = 0,0001 × 90000 + 1/81 × 27 = 9 + 27/81 = 9 + 1/3 = 9⅓
Y=60:4=15
Y=90:15=9
Z=17:10=1.7
U=-1.4