特殊三角函数数值表

1、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 = (tanA+tanB/(1-tanAtanB tan(A-B = (tanA-tanB/(1+tanAtanB cot(A+B = (cotAcotB-1/(cotB+cotA cot(A-B = (cotAcotB+1/(cotB-cotA三倍角公式 sin3A = 3sinA-4(sinA3; cos3A = 4(cosA3 -3cosA

2、tan3a = tan a tan(/3+a tan(/3-a 半角公式 sin(A/2 = (1-cosA/2 cos(A/2 = (1+cosA/2 tan(A/2 = (1-cosA/(1+cosA cot(A/2 = (1+cosA/(1-cosA tan(A/2 = (1-cosA/sinA=sinA/(1+cosA 和差化积 sin(a+sin(b = 2sin(a+b/2cos(a-b/2 sin(a-sin(b = 2cos(a+b/2sin(a-b/2 cos(a+cos(b = 2cos(a+b/2cos(a-b/2 cos(a-cos(b = -2sin(a+b/2sin

3、(a-b/2 tanA+tanB=sin(A+B/cosAcosB 积化和差 sin(asin(b = -1/2*cos(a+b-cos(a-b cos(acos(b = 1/2*cos(a+b+cos(a-b sin(acos(b = 1/2*sin(a+b+sin(a-b cos(asin(b = 1/2*sin(a+b-sin(a-b 诱导公式 sin(-a = -sin(a cos(-a = cos(a sin(/2-a = cos(a cos(/2-a = sin(a sin(/2+a = cos(a cos(/2+a = -sin(a sin(-a = sin(a cos(-a =

4、 -cos(a sin(+a = -sin(a cos(+a = -cos(a tgA=tanA = sinA/cosA 万能公式 sin(a = 2tan(a/2 / 1+tan(a/22 cos(a = 1-tan(a/22 / 1+tan(a/22 tan(a = 2tan(a/2/1-tan(a/22 asin(a+bcos(a = (a2+b2*sin(a+c 其中，tan(c=b/a asin(a-bcos(a = (a2+b2*cos(a-c 其中，tan(c=a/b 1+sin(a = sin(a/2+cos(a/22; 1-sin(a = sin(a/2-cos(a/22;这

5、是高考用的正割函数与余割函数正割函数在y=secx中，以x的任一使secx有意义的值与它对应的y值作为(x，y在直角坐标系中作出的图形叫正割函数的图像，也叫正割曲线y=secx的性质：(1定义域,x|x/2+k,kZ (2值域,secx1即secx1或secx1; (3y=secx是偶函数，即sec(x=secx图像对称于y轴; (4y=secx是周期函数周期为2k(kZ，且k0，最小正周期T=2并附上很难找到的正割图像.(正割函数图像中值域在-1到1之间的图像不包括。 更好的图像请参考正割与余弦互为倒数，余割与正弦互为倒数。正割函数无限趋向于直线x=/2+k。正割函数是无界函数正割函数的导数：(secx=secx*tanx 正割函数的不定积分：secxdx=|secx+tanx|+C余割函数对于任意一个实数x，都对应着唯一的角（弧度制中等于这个实数），而这个角又对应着唯一确定的余割值cscx与它对应，按照这个对应法则建立的函数称为余割函数。记作f(x=cscx 余割函数的性质1、定义域：x|xk，kZ