(3)对数函数f(x)?logax,f(xy)?f(x)?f(y),f(a)?1(a?0,a?1). (4)幂函数f(x)?x?,f(xy)?f(x)f(y),f'(1)??.
(5)余弦函数f(x)?cosx,正弦函数g(x)?sinx,f(x?y)?f(x)f(y)?g(x)g(y),
f(0)?1,limx?0g(x)?1. x29.几个函数方程的周期(约定a>0)
(1)f(x)?f(x?a),则f(x)的周期T=a; (2)f(x)?f(x?a)?0,或f(x?a)?1或?211(f(x)?0),或f(x?a)??(f(x)?0), f(x)f(x)f(x)?f2(x)?f(x?a),(f(x)??0,1?),则f(x)的周期T=2a;
1(f(x)?0),则f(x)的周期T=3a;
f(x?a)f(x1)?f(x2)且f(a)?1(f(x1)?f(x2)?1,0?|x1?x2|?2a),则f(x)的周期
1?f(x1)f(x2)(3)f(x)?1?(4)f(x1?x2)?T=4a;
(5)f(x)?f(x?a)?f(x?2a)f(x?3a)?f(x?4a)
?f(x)f(x?a)f(x?2a)f(x?3a)f(x?4a),则f(x)的周期T=5a;
(6)f(x?a)?f(x)?f(x?a),则f(x)的周期T=6a. 30.分数指数幂 (1)a?mn1nam(a?0,m,n?N,且n?1).(2)a??mn?1amn(a?0,m,n?N?,且n?1).
32.有理指数幂的运算性质
(1)ar?as?ar?s(a?0,r,s?Q).(2)(ar)s?ars(a?0,r,s?Q).(3)
(ab)r?arbr(a?0,b?0,r?Q).
注:若a>0,p是一个无理数,则ap表示一个确定的实数.上述有理指数幂的运算性质,对于无理数指数幂都适用.
45.同角三角函数的基本关系式
sin2??cos2??1,tan?=
sin?,tan??cot??1. cos?46.正弦、余弦的诱导公式
n?n??(?1)2sin?,sin(??)?? n?12?(?1)2cos?,?(n为偶数) (n为奇数) (n为偶数) (n为奇数)
47.和角与差角公式
sin(???)?sin?cos??cos?sin?;cos(???)?cos?cos?msin?sin?; tan(???)?tan??tan?.sin(???)sin(???)?sin2??sin2?(平方正弦公式);
1mtan?tan?cos(???)cos(???)?cos2??sin2?.
asin??bcos?=a2?b2sin(???)(辅助角?所在象限由点(a,b)的象限决定,tan??48.二倍角公式
b). asin2??sin?cos?.cos2??cos2??sin2??2cos2??1?1?2sin2?.tan2??49.三倍角公式
sin3??3sin??4sin3??4sin?sin(??)sin(??).
33cos3??4cos3??3cos??4cos?cos(??)cos(??).333tan??tan3???tan3???tan?tan(??)tan(??). 21?3tan?332tan?. 21?tan?????50.三角函数的周期公式
函数y?sin(?x??),x∈R及函数y?cos(?x??),x∈R(A,ω,?为常数,且A≠0,ω>0)的周期T?0)的周期T?2??;函数y?tan(?x??),x?k???2,k?Z(A,ω,?为常数,且A≠0,ω>
?. ?51.正弦定理?
abc???2R. sinAsinBsinC52.余弦定理
a2?b2?c2?2bccosA;b2?c2?a2?2cacosB;c2?a2?b2?2abcosC.
191.函数y?f(x)在点x0处的导数的几何意义
函数y?f(x)在点x0处的导数是曲线y?f(x)在P(x0,f(x0))处的切线的斜率f?(x0),相应的切线方程是y?y0?f?(x0)(x?x0).
192.几种常见函数的导数 (1)C??0(C为常
数).(2)(xn)'?nxn?1(n?Q).(3)(sinx)??cosx.(4)(cosx)???sinx.(5)(lnx)??1e(logax)??loga(6)(ex)??ex;(ax)??axlna.
x1;x193.导数的运算法则
u'u'v?uv'(v?0). (1)(u?v)?u?v.(2)(uv)?uv?uv.(3)()?vv2''''''194.复合函数的求导法则
设函数u??(x)在点x处有导数ux'??'(x),函数y?f(u)在点x处的对应点U处有导数
'''yu'?f'(u),则复合函数y?f(?(x))在点x处有导数,且yx?yu?ux,或写作
fx'(?(x))?f'(u)?'(x).