1) sin^2 п\8+ cos^2 3п\8+sin^2 5п\8+ cos^2 7п\8 2) tg 435+tg375 3) tg 225-tg 195 4) ctg (13п/12)-ctg(5п/12) 5) sin (2x+5п\4) при tg x=2\3 6) cos (2x+7п\4) при ctg x=2\3 7) sin2x при sinx-cosx=p не жалко,но вот решите

1)(1-сosπ/4)/2+(1+cos3π/4)/2+(1-cos5π/4)/2+(1+cos7π/4)=
1/2*(1-√2/2+1-√2/2+1+√2/2+1+√2/2)=1/2*4=2
2)tg75+tg15=sin(75+15)/[cos75cos15]=sin90:[1/2*(cos60+cos90)]=
=1:(1/2*1/2)=1:1/4=4
3)tg45-tg15=sin(45-15):[1/2*(cos30+cos60)]=1/2:(1/4*(√3+1)=2(√3+1)
4)ctgπ/12-ctg5π/12=sin(π/12-5π/12):[1/2*(cosπ/3-cosπ/2)]=
=-√3/2:[1/2*1/2)=-√3/2*4=-2√3
5)cos²x=1:(1+tg²x)=1:(1+4/9)=9/13
cosx=3/√13
sinx=√(1-cos²x)=√(1-9/13)=2/√13
sin2x=2*sinxcosx=2*2/√13*3/√13=12/√13
cos2x=cos²x-sin²x=9/13-4/13=5/13
sin(2x+5π/4)=-sin(2x+π/4)=-sin2x*cosπ/4-cos2x*sinπ/4=
=-12/13*√2/2-5/13*√2/2=--17√2/26
6)sin²x=1:(1+ctg²x)=1:(1+4/9)=9/13
sinx=3/√13
cosx=2/√13
cos2x=cos²x-sin²x=4/13-9/13=-5/13
sin2x=2sinxcosx=12/√13
cos(2x+7π/4)=cos(2x-π/4)=cos2xcosπ/4+sin2xsinπ/4=
=-5/13*√2/2+12/13*√2/2=7√2/13
7)sin2x=1-(sinx-cosx)²=1-p²