诚心求教数学,希望帮帮忙~~1.已知α、β属于(3π/4,π),sin(α+β)=-3/5,sin(β-π/4)=12/13,则cos(α+π/4)等于()A.16/65 B.56/65 C.-16/65 D.56/652.已知α,β属于(0,π),tan(α-β)=1/2,tanβ=-1
来源:学生作业帮助网 编辑:作业帮 时间:2024/09/10 14:34:42
xY[o+hEL6/S >(Z,ŋHJ.Hɤ.%Z❀ggvߙ]R(ЧEΜ93O~6Jl%Ƿ.:Rf&}{g8n.jd0H浟_m`\hD#{|uP[t._}?JnE<մ)+\*5+U
"t{Iʅ_e @!N}kLsAm5q+ uYfbI*<W06E@}"Βt,&i-ɜ^bk_Jq)&b9ؼ>?kiء?`y!jq6^cLJ^5vQ\_?$$O~+/0V/k6KђmJI氠zuަO%e9
2e6'MUf
_߷og7Ri"ZI!!3+Ӥ?"Abn8Jq[/ cz=mH76Q/sRa_S9 (ڙ1S*|KHCMCzǐ'lʌTz3y< A՞u#TRR?wvy&
Xz9nǴrbu^nK2Sc-cb2A9p@dUP /
|+^ç4w)\:9deάb
^=0E1o`&%]P+Ȟa
vAeY7;wN^vY/qRRL8GND-ƍ<'=Or\e
I9y&$dݨߞ7-*@EqV w
oSBּDsl
EA8]acIU{b4sP:J#cx}e!:K?2"}FI)r "C!=v$0*"Pm$@~8 MxpN6qYhR .♝>3ҏAǚ*'ާI]bu YzD `DWB3E =I?:pRitYR#rFf+?zS`d*N@w$A8BDTRR0KK<&*Aϛ4A/Uuv-~w7(A
fJFL+lV I!( Tm>whUj.hzt
Rri_1| ž ixV.G(WАZR*['Lv@+"+&=kƯBAVeRA>z$̒i{62uTe-scEal1i!Z