Question

Zadanie w załączniku!

Answer 1

c.ctgα=21/20

tgα=sinα/cosα

20/21=sinα/cosα

sinα=20/21cosα

sin²α+cos²α=1-jedynka trygonometryczna

400/441cos²α+cos²α=1

841/441cos²α=1

c0s²α=441/841

c0sα=21/29

sinα=20/21×21/29=20/29

d.tgα=15/8

tgα=sinα/cosα

15/8=sinα/cosα

sinα=15/8cosα

sin²α+cos²α=1

225/64cos²α+cos²α=1

289/64cos²α=1

c0s²α=64/289

c0sα=8/17

sinα=15/8×8/17=15/17