6. 1)cos²α+cos²(90°-α)=cos²α+sin²α=1
2) sin²α-cos²(90°-α)= sin²α- sin²α=0
7. sin70°≈0.9397
cos55°≈0.5736
tg10°≈0.1763
ctg18°≈3.0777
8. х=8°
6. 1)cos²α+cos²(90°-α)=cos²α+sin²α=1
2) sin²α-cos²(90°-α)= sin²α- sin²α=0
7. sin70°≈0.9397
cos55°≈0.5736
tg10°≈0.1763
ctg18°≈3.0777
8. х=8°