2log²2 (sinx)-5log2 (sinx)-3=0
subst.: log2 (sinx)=z
2z²-5z-3=0,D=25+24=49,√D=√49=7
a)z1=(5+7)/4=12/4=3
log2(sinx)=3, sinx=2³=8 ne dact rešenie ( /sinx/≤1)
b)z2=(5-7)/4=-2/4=-1/2
log2 (sinx)=-1/2, sinx=2ˇ(-1/2)=1/(2ˇ(1/2))=1/√2=(√2)/2
x1=π/4+2kπ
x2=3π/4 +2kπ, k∈Z