Sinπ/4=cosπ/4=√2/2
1
(sinπ/4cosa+cosπ/4sina-cosπ/4cosa+sinπ/4sina)/(sinπ/4cosa+cosπ/4sina+cosπ/4cosa-sinπ/4sina)=√2/2(cosa+sina-cosa+sina)/√2/2(cosa+sina+cosa-sina)=2sina/2cosa=tga
2
(sinπ/4cosa-cosπ/4sina+cosπ/4cosa-sinπ/4sina)/(sinπ/4cosa-cosπ/4sina-cosπ/4cosa-sinπ/4sina)=√2/2(cosa-sina+cosa+sina)/√2/2(cosa-sina-cosa-sina)=2cosa/(-2sina)=-ctga