所有初中高中三角函数公式大全(共7页).doc
精选优质文档-倾情为你奉上第一部分 三角函数公式·两角和差的三角函数 cos(+)=cos·cos-sin·sin cos(-)=cos·cos+sin·sin sin(±)=sin·cos±cos·sin tan(+)=(tan+tan)/(1-tan·tan) tan(-)=(tan-tan)/(1+tan·tan) ·公式: sin+sin=2sin(+)/2cos(-)/2 sin-sin=2cos(+)/2sin(-)/2 cos+cos=2cos(+)/2cos(-)/2 cos-cos=-2sin(+)/2sin(-)/2 ·公式: sin·cos=(1/2)sin(+)+sin(-) cos·sin=(1/2)sin(+)-sin(-) cos·cos=(1/2)cos(+)+cos(-) sin·sin=-(1/2)cos(+)-cos(-) ·: sin(2)=2sin·cos=2/(tan+cot) cos(2)=(cos)2-(sin)2=2(cos)2-1=1-2(sin)2 tan(2)=2tan/(1-tan2) cot(2)=(cot2-1)/(2cot) csc(2)=1/2*sec·cscsec(2)=sec2/(1-tan2) ·三倍角公式: sin(3) = 3sin-4sin3 = 4sin·sin(60°+)sin(60°-) cos(3) = 4cos3-3cos = 4cos·cos(60°+)cos(60°-) tan(3) = (3tan-tan3)/(1-3tan2) = tantan(/3+)tan(/3-) cot(3)=(cot3-3cot)/(3cot2-1) ·n倍角公式: sin(n)=ncos(n-1)·sin-C(n,3)cos(n-3)·sin3+C(n,5)cos(n-5)·sin5- cos(n)=cosn-C(n,2)cos(n-2)·sin2+C(n,4)cos(n-4)·sin4- ·: sin(/2)=±(1-cos)/2) cos(/2)=±(1+cos)/2) tan(/2)=±(1-cos)/(1+cos)=sin/(1+cos)=(1-cos)/sin cot(/2)=±(1+cos)/(1-cos)=(1+cos)/sin=sin/(1-cos) sec(/2)=±(2sec/(sec+1) csc(/2)=±(2sec/(sec-1) ·辅助角公式: Asin+Bcos=(A2+B2)sin(+)(tan=B/A) Asin+Bcos=(A2+B2)cos(-)(tan=A/B) ·万能公式 sin(a)= (2tan(a/2)/(1+tan2(a/2) tan(a)= (2tan(a/2)/(1-tan2(a/2) cos(a)= (1-tan2(a/2)/(1+tan2(a/2)·降幂公式 sin2=(1-cos(2)/2=versin(2)/2 cos2=(1+cos(2)/2=covers(2)/2 tan2=(1-cos(2)/(1+cos(2) ·三角和的三角函数: sin(+)=sin·cos·cos+cos·sin·cos+cos·cos·sin-sin·sin·sin cos(+)=cos·cos·cos-cos·sin·sin-sin·cos·sin-sin·sin·cos tan(+)=(tan+tan+tan-tan·tan·tan)/(1-tan·tan-tan·tan-tan·tan) ·两角和与差的三角函数 cos(+)=cos·cos-sin·sin cos(-)=cos·cos+sin·sin sin(±)=sin·cos±cos·sin tan(+)=(tan+tan)/(1-tan·tan) tan(-)=(tan-tan)/(1+tan·tan) ·公式: sin+sin=2sin(+)/2cos(-)/2 sin-sin=2cos(+)/2sin(-)/2 cos+cos=2cos(+)/2cos(-)/2 cos-cos=-2sin(+)/2sin(-)/2 ·公式: sin·cos=(1/2)sin(+)+sin(-) cos·sin=(1/2)sin(+)-sin(-) cos·cos=(1/2)cos(+)+cos(-) sin·sin=-(1/2)cos(+)-cos(-) ·: sin(2)=2sin·cos=2/(tan+cot) cos(2)=(cos)2-(sin)2=2(cos)2-1=1-2(sin)2 tan(2)=2tan/(1-tan2) cot(2)=(cot2-1)/(2cot) sec(2)=sec2/(1-tan2) csc(2)=1/2*sec·csc ·三倍角公式: sin(3) = 3sin-4sin3 = 4sin·sin(60°+)sin(60°-) cos(3) = 4cos3-3cos = 4cos·cos(60°+)cos(60°-) tan(3) = (3tan-tan3)/(1-3tan2) = tantan(/3+)tan(/3-) cot(3)=(cot3-3cot)/(3cot2-1) ·n倍角公式: sin(n)=ncos(n-1)·sin-C(n,3)cos(n-3)·sin3+C(n,5)cos(n-5)·sin5- cos(n)=cosn-C(n,2)cos(n-2)·sin2+C(n,4)cos(n-4)·sin4- ·: sin(/2)=±(1-cos)/2) cos(/2)=±(1+cos)/2) tan(/2)=±(1-cos)/(1+cos)=sin/(1+cos)=(1-cos)/sin cot(/2)=±(1+cos)/(1-cos)=(1+cos)/sin=sin/(1-cos) sec(/2)=±(2sec/(sec+1) csc(/2)=±(2sec/(sec-1) ·辅助角公式: Asin+Bcos=(A2+B2)sin(+)(tan=B/A) Asin+Bcos=(A2+B2)cos(-)(tan=A/B) ·万能公式 sin(a)= (2tan(a/2)/(1+tan2(a/2) cos(a)= (1-tan2(a/2)/(1+tan2(a/2) tan(a)= (2tan(a/2)/(1-tan2(a/2) ·降幂公式 sin2=(1-cos(2)/2=versin(2)/2 cos2=(1+cos(2)/2=covers(2)/2 tan2=(1-cos(2)/(1+cos(2) ·三角和的三角函数: sin(+)=sin·cos·cos+cos·sin·cos+cos·cos·sin-sin·sin·sin cos(+)=cos·cos·cos-cos·sin·sin-sin·cos·sin-sin·sin·cos tan(+)=(tan+tan+tan-tan·tan·tan)/(1-tan·tan-tan·tan-tan·tan) ·其它公式 1+sin(a)=(sin(a/2)+cos(a/2)2 1-sin(a)=(sin(a/2)-cos(a/2)2 csc(a)=1/sin(a) sec(a)=1/cos(a) cos30=sin60 sin30=cos60 ·推导公式 tan+cot=2/sin2 tan-cot=-2cot2 1+cos2=2cos2 1-cos2=2sin2 1+sin=sin(/2)+cos(/2)21+sin(a)=(sin(a/2)+cos(a/2)2 1-sin(a)=(sin(a/2)-cos(a/2)2 csc(a)=1/sin(a) sec(a)=1/cos(a) cos30=sin60 sin30=cos60 ·推导公式 tan+cot=2/sin2 tan-cot=-2cot2 1+cos2=2cos2 1-cos2=2sin2 1+sin=sin(/2)+cos(/2)2貌似就这么多了 专心-专注-专业