f(x)=x(2x π) 2cosx的间断点并判别类型

f(x)=cos(-2x+a)(-π

∵f（x）＝cos（2x－π/3）＋（sinx）^2－（cosx）^2＝cos（2x－π/3）－cos2x＝2sin（2x－π/6）sin（π/6）＝sin（2x－π/6）.∴g（x）＝［sin（2x

f(x)=[1+cos2x)/2]/[1+(1-cos2x)/2]=(1+cos2x)/(3-cos2x)=-1+4/(3-cos2x)f'(x)=-4/(2-cos2x)^2*(2-cos2x)'=

f(x)=(1/2^0)·sin(x/2)+(2^0)·cos(2x)f‘(x)=(1/2)·cos(x/2)+(-2)·sin(2x)=(1/2^1)·cos(x/2)+(-2^1)·sin(2x)

1)f(x)=1+cos(2x+π/3)-(1+cos2x)/2=1/2-sin2x根号3/2最小值1/2-根号3/2最小正周期π2）c带入得sinC=根号3/2C=π/3A=π-B-C=2π/3-a

根据公式：COS^2a=(1+COS2a)/2a=(X+π/12)说句不好听的,你还是基本知识没掌握好,不会活用知识.希望你多背多看,看清题,把公式活用.

f(x)=√2sin（2 x-π/4）+2f(x)max=√2+2；此时X=3π/8令（2 x-π/4）∈【-π/2,π/2】,解得x∈【-π/8,3π/8】,因为x∈(0&nbs

设x0所以f(-x)=sin2(-x)+cos(-x)=-sin2x+cosx因为f(x)为奇函数,所以f(-x)=-f(x)得f(x)=-f(-x)=sin2x-cosx(x

f(x)=cos(2π-x)-x³sin1/2x=cosx-x³sin1/2x函数定义域为Rf(-x)=cos(-x)-(-x)³sin(-1/2x)=cosx-x

f(x)=cos(3x)*cos(2x)+sin(3x)*sin(2x)=cos(3x-2x)=cosxf'(x)=-sinx

f'(sinx)=cos²x=1-sin²xf'(x)=1-x²f(x)=x-x^3/3

令F’(x)=√3cos2x+sin2x=0,x1=kπ/2-π/6(k为偶数),x2=kπ/2-π/6(k为奇数)∴f(x)在x1极小,在x2处取极大值∴f(x)单调递减区间为[kπ/2-π/6,（

f(x)=cos(-x/2)+sin(π-x/2)=cosx/2+sinx/2f(a)=cos(a/2)+sin(a/2)=（2√10）/5cos(a/2)+sin(a/2)=（2√10）/5平方1+

f'(x)=-1/2*sin(x/2)*[sin(x/2)-cos(x/2)]+cos(x/2)[1/2cos(x/2)+1/2sin(x/2)]=-1/2*sin²(x/2)+1/2sin

f(x)=cos(2x-π/3)-(cos^2x-sin^2x)=cos(2x-π/3)-cos2x=2sin(2x-π/6)sinπ/6=sin(2x-π/6)因为y=sinx的单减区间为[π/2+

f(x)=cos(2x-π\3)+sin²x-cos²x=1/2cos2x+√3/2sin2x-cos2x=√3/2sin2x-1/2cos2x=-cos(2x+π\3)-1

f(x)=sin(2x)+√2cos(x-π/4)=sin(2x)+√2[cosxcos(π/4)+sinxsin(π/4)]=sin(2x)+cosx+sinx=sin(2x)+√2sin(x+π/

你确定第一个符号是加号不是乘号?

（1）f(x)=2cos(x/2)·(sin(x/2)+cos(x/2))-1=2cos(x/2)·sin(x/2)+2cos^2(x/2)-1=sinx+cosx(倍角公式)=√2sin(x+π/4

（1）f(x)=2nm+b=2（cosx/2的平方+cosx/2*sinx/2）+b=cosx+1+sinx+b(运用到正弦余弦的二倍角公式)=（根号2）*sin(x+45°)+1+b正弦的增区间在[