1, sin (x + y) = sinx . cosy + cosx . siny
2, sin (x – y) = sinx . cosy – cosx . siny
3, cos (x + y) = cosx . cosy – sinx . siny
4, cos (x – y) = cosx . cosy + sinx . siny
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sinx sin (x + k2?)
tgx = –––– = ––––––––––– = tg (x + k2?)
cosx cos (x + k2?)
cosx cos (x + k2?)
cotg = ––––– = ––––––––––– = cotg (x + k2?)
sinx sin (x + k2?)
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sin ( – x) = – sinx
cos ( – x) = cosx
tg ( – x) = – tgx
cotg ( – x) = – cotgx
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tgx . cotgx = 1
cos2x + sin2x = 1
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sínusová veta
a b c
–––– = –––– = ––––
sin ? sin ? sin ?
kosínusová veta
a2 = b2 + c2 – 2bc . cos ?
b2 = a 2 + c2 – 2ac . cos ?
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sin2x = 2sinx . cosx
cos2x = cos2x – sin2x