Create successful ePaper yourself
Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.
sin x
23) tgx =
cos x
cos x
24) ctgx =
sin x = 1
tg x
25) tg(a + b) =
tga + tgb
1 − tga ∙ tgb
26) tg2x = 2tgx
1 − tg x
27) tg(a − b) =
tga − tgb
1 + tga ∙ tgb
tga + tgb + tgc − tga ∙ tgb ∙ tgc
28) tg(a + b + c) =
1 − tga ∙ tgb − tgb ∙ tgc − tgc ∙ tga
29) ctg(a + b) =
ctga ∙ ctgb − 1
ctgb + ctga
30) ctg2x = ctg x − 1
2ctgx
31) ctg(a − b) =
ctga ∙ ctgb + 1
ctgb − ctga
32) tg x 2 = sinx
1 + cosx = 1 − cosx
sinx
33) sinx = 2tg x 2
1 + tg x 2
34) cosx = 1 − x
tg 2
1 + tg x 2
35) tgx = 2tg x 2
1 − tg x 2
36) sin π − x = cosx
2
37) cos π − x = sinx
2
38) tg π − x = ctgx
2
2