Question

Решите пожалуйста!!!!

Answer 1

1) cos 11π/6=cos(3π/2+π/3)=sin π/3=√3/2 (4 четверть).

  sin 7π/4=sin(3π/2+π/4)=-cos π/4=-√2/2 (4 четверть).

√3/2 + √2/2=(√3+√2)/2.

2) cosx=-√3/2; x=+-5π/6+2πn; n∈Z.

3) log₀,₂40 - log₀,₂8=log₀,₂40/8=log₀,₂5=-1     (0,2=1/5).