求值：cos(π/13)+cos(3π/13)+cos(9π/13)我要的结果当然不是近似值而应该是精确值了！同时要有简略的解题过程。
来源：学生作业帮助网 编辑：作业帮 时间：2024/10/19 10:02:51
xURH^vqbeY*̬r\ƮT d b d'Xa an+eHRe]Wxre$qS Iiºsw g.=p 8V՚źc %
pzn]9ĶO ]p ԼUp4۟BIY
Oik&6rs}Vr?C̱8 Уm=m 9=X* M O :ޱӻt ֏E
NF&P<8 FHxR,&{
-9to6d" Zxn 3H3%oT
삺'ŊN{W'_enLFDf*t : j9kW|}з.J]n$.E*Ou= ߰P\6_tR.89:vw76G*XjvHAn\Z 7MFcѯx 2d 磛]3*"48S(:J2/xI
)LW?dq^9X b,HCCa4
^ ՊR-*x$gҭ5_c8kb8 Yр3Y! Pt4 O'TO
{
N֯bb1 5kxV1r~^ZfV^Q
>3Ϭ}m JD=hs`1 lנO+B -2 =ͷn;/}ˍb{F[R dϠWl=dB ,0=!U 0/,4wۣ ̞s j<}ԋ4;Y^z-Imb R`$Xҁ%ބz[ke_;~9v&3Z_
cos(3π/2 - π/3),求值
cos（-8π/3）求值
cos（-8π/3）求值
求值:cos(π/11)cos(2π/11)cos(3π/11)cos(4π/11)cos(5π/11)
求值：cos(π/11)-cos(2π/11)+cos(3π/11)-cos(4π/11)+cos(5π/11)
COS(π/7)+COS(3π/7)+COS(5π/7)化简求值,
求值：cos²A+cos²（2π/3+A)+cos²(2π/3-A)
求值:cos(arcsin1/3)
求值:sin(26π/3)+cos(-17π/4)=
求值：sin(π/12)+cos(π/12)
求值cos5π/8*cosπ8
求值：cos（25π /4）
求值:cos(-6分之31π)
tanπ/8+cosπ/8求值求值,
8sin(π/32)cos(π/32)cos(π/16)cos(π/8),求值
化简求值cos(π/7)cos(2π/7)cos(4π/7)
求值sin10π/3-根号2cos(-19π/4)+tan(13π/3)
求值:cos(arcsin1/3)=