Sin (d-b) / tgd-tgb=cosd*cosb

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17 апреля, 01:18

Sin (d-b) / tgd-tgb=cosd*cosb

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Борюня · Answer 1

cosa=±Ö1-sin2a = (1-tg2a/2) / (1+tg2a/2) sina=±Ö1/1+ctg2a = (2tga/2) / (1+tg2a/2) cos (ab) = sinasinbcosacosb sin (a±b) = sinacosb±sinbcosa tg (a+b) = sin (a+b) / cos (a+b) = (tga+tgb) / (1-tgatgb) tg (a-b) = (tga-tgb) / (1+tgatgb) ctg (a+b) = (ctgactgb-1) / (ctga+ctgb) ctg (a-b) = (ctgactgb+1) / (ctgb-ctga) sin2a=2sinacosa = (2tga) / (1+tg2a) cos2a=cos2a-sin2a = (1-tg2a) / (1+tg2a) = 2cos2a-1=1-2sin2a tg2a=2tga / (1-tg2a) ctg2a = (ctg2a-1) / 2ctga ctg2a = (ctg2a-1) / 2ctga cos2a/2=1+cosa/2 cos2a = (1+cos2a) / 2 sin2a/2=1-cosa/2 sin2a = (1-cos2a) / 2 cosa/2=±Ö1+cosa/2 sina/2=±Ö1-cosa/2 tga/2=±Ö1-cosa/1+cosa = (sina) / (1+cosa) = (1-cosa) / sina ctga/2=±Ö1+cosa/1-cosa=sina / (1-cosa) = (1+cosa) / sina sina+cosa=Ö2 cos (P/4-a) sina-cosa=Ö2 sin (a-P/4) cosa-sina=Ö2 sin (P/4-a) cosa+cosb=2cos (a+b) / 2cos (a-b) / 2 cosa-cosb=-2sin (a+b) / 2sin (a-b) / 2 sina+sinb=2sin (a+b) / 2cos (a-b) / 2 sina-sinb=2sin (a-b) / 2cos (a+b) / 2 tga±tgb = (sin (a±b)) / cosacosb cosacosb=1/2 (cos (a-b) + cos (a+b)) sinasinb=1/2 (cos (a-b) - cos (a+b)) sinacosb=1/2 (sin (a+b) + sin (a-b)) tga = (2tga/2) / (1-tg2a/2) cosa=±Ö1-sin2a = (1-tg2a/2) / (1+tg2a/2) sina=±Ö1/1+ctg2a = (2tga/2) / (1+tg2a/2) cos (ab) = sinasinbcosacosb sin (a±b) = sinacosb±sinbcosa tg (a+b) = sin (a+b) / cos (a+b) = (tga+tgb) / (1-tgatgb) tg (a-b) = (tga-tgb) / (1+tgatgb) ctg (a+b) = (ctgactgb-1) / (ctga+ctgb) ctg (a-b) = (ctgactgb+1) / (ctgb-ctga) sin2a=2sinacosa = (2tga) / (1+tg2a) cos2a=cos2a-sin2a = (1-tg2a) / (1+tg2a) = 2cos2a-1=1-2sin2a tg2a=2tga / (1-tg2a) ctg2a = (ctg2a-1) / 2ctga ctg2a = (ctg2a-1) / 2ctga cos2a/2=1+cosa/2 cos2a = (1+cos2a) / 2 sin2a/2=1-cosa/2 sin2a = (1-cos2a) / 2 cosa/2=±Ö1+cosa/2 sina/2=±Ö1-cosa/2 tga/2=±Ö1-cosa/1+cosa = (sina) / (1+cosa) = (1-cosa) / sina ctga/2=±Ö1+cosa/1-cosa=sina / (1-cosa) = (1+cosa) / sina sina+cosa=Ö2 cos (P/4-a) sina-cosa=Ö2 sin (a-P/4) cosa-sina=Ö2 sin (P/4-a) cosa+cosb=2cos (a+b) / 2cos (a-b) / 2 cosa-cosb=-2sin (a+b) / 2sin (a-b) / 2 sina+sinb=2sin (a+b) / 2cos (a-b) / 2 sina-sinb=2sin (a-b) / 2cos (a+b) / 2 tga±tgb = (sin (a±b)) / cosacosb cosacosb=1/2 (cos (a-b) + cos (a+b)) sinasinb=1/2 (cos (a-b) - cos (a+b)) sinacosb=1/2 (sin (a+b) + sin (a-b)) tga = (2tga/2) / (1-tg2a/2