Răspuns:
Explicație pas cu pas:
a) sin 30 grade ori tg 45 grade + cos 30 grade ori ctg 60 grade=
=1/2.×1+1/2×1=1/2+1/2=1
b) sin 60 grade ori cos 60 grade + sin 30 grade ori cos 30 grade - sin 45 grade ori cos 45 grade.=√3/2×1/2+1/2×√3/2-√2/2√2/2=2×√3/2-1/2=
=√3-1