sqrt(2)sin(90-15)-sqrt(2)sin(15)=sqrt(2)(cos15-sin15)=sqrt(2)(cos(45-30)-sin(45-30))=
=sqrt(2)(cos45cos30+sin45sin30-sin45cos30+sin30cos45=2sin45sin30)=1
sqrt(2)sin(90-15)-sqrt(2)sin(15)=sqrt(2)(cos15-sin15)=sqrt(2)(cos(45-30)-sin(45-30))=
=sqrt(2)(cos45cos30+sin45sin30-sin45cos30+sin30cos45=2sin45sin30)=1