1,
sin^230+tg^230=(\frac{1}{2})^2+(\frac{\sqrt3}{3})^2=\frac{1}{4}+\frac{3}{9}=\frac{3}{12}+\frac{4}{12}=\frac{7}{12}
2,
cos^260+cos^245+cos^230=(\frac{1}{2})^2+(\frac{\sqrt2}{2})^2+(\frac{\sqrt3}{2})^2=\frac{1}{4}+\frac{2}{4}+\frac{3}{4}=\frac{6}{4}=1,5
3,
sin^215+sin^275=sin^215+sin^2(90-15)=sin^215+cos^215=1