Verified answer

Ответ:v(π/3)=3/8 м/с.

Объяснение:

s=-3*cos((t/4)+(π/12))+10

v=s'=(-3*cos((t/4)+(π/12))+10)'=3*sin((t/4)+(π/12))*((t/4)+(π/12))'=

=3*sin((t/4)+(π/12))*(1/4)=

v(π/3)=3*sin((π/(3*4))+(π/12))/4=3*sin((π/12)+(π/12))/4=

=3*sin(π/6)/4=3/(2*4)=3/8.