30 (х+6) = 330
30 х +180 = 330
30 х = 330 - 180
30 х = 150
х = 150/30
х = 5 м/хв
_5751|639
5751|1
0
Не ужели так трудно
(sinπ/7*cosπ/7*cos2π/7*cos3π/7)/(sinπ/7)=
=(sin2π/7*cos2π/7*cos3π/7)/(2sinπ/7)=(sin4π/7*cos3π/7)/(4sinπ/7)=
=(sin(π-3π/7)*cos3π/7)/(4sinπ/7)=(sin3π/7*cos3π/7)/4sinπ/7)=
=(sin6π/7)/(8sinπ/7)=sin(π-π/7)/(8sinπ/7)=(sinπ/7)/(8sinπ/7)=1/8
45+65=110
65-на 20 больше,чем 45
1/20 или 0.5 играет в шахматы