高中三角函数公式大全 三角函数公式 两角和公式 sin(A+B) = sinAcosB+cosAsinB sin(A-B) = sinAcosB-cosAsinB cos(A+B) = cosAcosB-sinAsinB cos(A-B) = cosAcosB+sinAsinB tan(A+B) =tanAtanB-1tanBtanA tan(A-B) =tanAtanB1tanBtanA cot(A+B) =cotAcotB1-cotAcotB cot(A-B) =cotAcotB1cotAcotB 倍角公式 tan2A =Atan12tanA2 Sin2A=2SinA•CosA Cos2A = Cos2A-Sin2A=2Cos2A-1=1-2sin2A 三倍角公式 sin3A = 3sinA-4(sinA)3 cos3A = 4(cosA)3-3cosA tan3a = tana·tan(3 +a)·tan(3 -a) 半角公式 sin(2A )=2cos1A cos(2A )=2cos1A tan(2A )=AAcos1cos1 cot(2A )=AAcos1cos1 tan(2A )=AAsincos1 =AAcos1sin 和差化积 sina+sinb=2sin2ba cos2ba sina-sinb=2cos2ba sin2ba cosa+cosb = 2cos2ba cos2ba cosa-cosb = -2sin2ba sin2ba tana+tanb=babacoscos)sin( 积化和差 sinasinb = -21 [cos(a+b)-cos(a-b)] cosacosb = 21 [cos(a+b)+cos(a-b)] sinacosb = 21 [sin(a+b)+sin(a-b)]