1)cosx-1=0, cosx=1, x=2kπ,k∈Z
2)tg3x=-1/√3, tg3x=-(√3)/3, 3x=-π/6+kπ, x=-π/18+kπ/3, k∈Z
3)cos(x+π/3)=-1, x+π/3=3π/2+2kπ, x=3π/2-π/3+2kπ=7π/6+2kπ,k∈Z
4)(cosx-cos(π/3)(sinx+4)=0
a)cosx-cos(π/3)=0, cosx=1/2, x=π/3+2kπ i tože x=5π/3+2kπ, k∈Z
b)sinx+4=0, sinx=-4 ne imeet rešenie.
5)cos²x+3sinx-3=0, (1-sin²x)+3sinx-3=0,-sin²x+3sinx-2=0
sin²x-3sinx+2=0, sinx=t, t²-3t+2=0, (t-1)(t-2)=0
a)t-1=0, sinx-1=0,sinx=1., x=π/2+2kπ,k∈Z
t-2=0, sinx-2=0, sinx=2, ne imeet rešenie.