sin 2a = 2sinaaacosaaa = 2 0 −1-1−1 = 0
cos 2a = cos^2aaa - sin^2aaa = −1-1−1^2 - 0 = 1
ctg a = cosaaa / sinaaa = -1 / 0 = undefined
ctg 2a = 1 / tg 2a = 1 / 2<em>sin(a)</em>cos(a)/(cos2(a)−sin2(a))2 <em> sin(a) </em> cos(a) / (cos^2(a) - sin^2(a))2<em>sin(a)</em>cos(a)/(cos2(a)−sin2(a)) = 1 / 0/(1−0)0 / (1 - 0)0/(1−0) = undefined
tg 2a = sin 2a / cos 2a = 0/1 = 0
sin 2a = 2sinaaacosaaa = 2 0 −1-1−1 = 0
cos 2a = cos^2aaa - sin^2aaa = −1-1−1^2 - 0 = 1
ctg a = cosaaa / sinaaa = -1 / 0 = undefined
ctg 2a = 1 / tg 2a = 1 / 2<em>sin(a)</em>cos(a)/(cos2(a)−sin2(a))2 <em> sin(a) </em> cos(a) / (cos^2(a) - sin^2(a))2<em>sin(a)</em>cos(a)/(cos2(a)−sin2(a)) = 1 / 0/(1−0)0 / (1 - 0)0/(1−0) = undefined
tg 2a = sin 2a / cos 2a = 0/1 = 0