sina+cosa=1
5/13+cosa=1
soca=1-5/13
cosa=8/13
tga=sina/cosa
tga=5/13÷8/13
tga=5/8
ctga=cosa/sina
ctga=8/5
sina+cosa=1
5/13+cosa=1
soca=1-5/13
cosa=8/13
tga=sina/cosa
tga=5/13÷8/13
tga=5/8
ctga=cosa/sina
ctga=8/5