y`=3^(u)*ln3*(u)`
y`=3^(cos2x)*ln3*(cos2x)`
y`=3^(cos2x)*ln3*(-sin2x)*(2x)`
y`=3^(cos2x)*ln3*(-sin2x)*2
y`(Pi/4)=3^(cos(Pi/2))*ln3*(-sin(Pi/2))*2=
=3^(0)*ln3(-1)*2=-2ln3
2
v(t)=x`(t)=((t+5)^(4/3))`=(4/3)*(t+5)^((4/3)-1)=
=(4/3)*(x+5)^(1/3)
a(t)=v`(t)=((4/3)*(x+5)^(1/3))`=(4/3)*(1/3)*(x+5)^((1/3)-1)=
=(4/9)*(x+5)^(-2/3)
a(3)=(4/9)*(3+5)^(-2/3)=(4/9)*8^(-2/3)=
=(4/9)*(2^(3))^(-2/3)=(4/9)*2^(-2)=(4/9)*(1/4)=1/9