化简:sin{33° x}cos{27° x}-搜答案-搜搜做题作业网

sin(x+y)cos(x-y)+cos(x+y)sin(x-y)=sin(x+y+x-y)=sin2x再问：sin(x+y)cos(x-y)+cos(x+y)sin(x-y)为什么=sin(x+y+

sin(π-x)+sin(π+x)-cos(-x)+cos(2π-x)-tan(π+x)cot(π-x)=-sin(-x)-sin（x）-cos(x)+cos(-x)-[-tan(x)][-cot(-

据:cos2(x)=cosx^2-sinx^2=2cosx^2-1得:2sin^2(x)sin^2(φ)+2cos^2(x)cos^2(φ)-cos2(x)cos^2(φ)=2sin^2(x)sin^

根据公式sin（a-b）=sinacosb-cosasinb所以原式=sin(x+105-x+15）=sin120°=√3/2

[2cos³x－sin²(360°－x)＋2sin(90°+x)+1]÷[2+2cos²(180°+x)+cos(－x)]=[2cos³x-sin²x

原式=cos[(x-25)-(65-x)]=cos(2x-90)=sin2x

这个方程无解取区间[-π,π]-1

cos(180°+x)*sin(x+360°)/[sin(-x-180°)*cos(-180°-x)]=-cosx×sinx/[-sin(180°+x)][cos(180°+x)]=-cosx×sin

=sin^2(x)*[cos^2(x)-1]=-sin^4(x)再答：别忘了负号再问：嗯谢谢

sin^4x-sin^2xcos^2x+cos^4x=sin^4x+2sin^2xcos^2x+cos^4x-3sin^2xcos^2x=(sin^2x+cos^2x)^2-3sin^2xcos^2x

3/2cosx-3/2(sinx)^2

原式=[sinx*(-cosx)*sinx]/[(-cosx)*sinx*(-sinx)]=-1

cos²（-X）-【tan（360°+X）】/【sin（-X）】=cos²X-tanX/-sinX=cos²X+1/cosX

[sin(180+x)-tan(-x)+tan(-360-x)]/[tan(x+180)+cos(-x)+cos(-x-180)]=[-sinx+tanx-tan(360+x)]/[tanx+cosx

y=sin²x+2sinxcosx+3cos²xy=(sin²x+cos²x)+2sinxcosx+(2cos²x-1)+1=1+sin2x+cos2

cos(33°-x)sin(63°-x)-cos(x+57°)sin(27°+x)=cos[90°-(x+57°)]sin[90°-(x+27°]-cos(x+57°)sin(x+27°)=sin(x

我来给你解答,稍等再答：

利用积化和差公式sinAcosB=(1/2)*[sin(A+B)+sin(A-B)]以及sin(-A)=-sinA的性质可得sin(x)(cos(x)+cos(3x)+cos(5x)+cos(7x))

2（√3/2sinx+1/2cosx)=2sin(x+π/6）√2*√2（√2/2sinx-√2/2cosx)=2sin(x-π/4）（3）解;2√2(1/2cosx-√3/2sinx)=2√2cos