Stim ca sin patrat de x + cos patrat de x = 1
Sin patrat de x = 0,3 x 0,3 = 3/10 x 3/10 = 9/100 = 0,09
Atunci cos patrat de x = 1 - 0,09 = 100/100 - 9/100 = 91/100
cos x = rad 91/10
tg x = sin x/cos x = (3/10)/(rad 91/10) = 3/10 x 10/rad 91 = 3/rad 91 = 3 rad 91/91
ctg x = cos x/ sin x = (rad 91/10)/(3/10) = rad 91/10 x 10/3 = rad 91/3
