Հանրահաշիվ

Ա) (sin12+cos18)^2+(cos12+sin18)^2=sin^2(12)+2sin12cos18+cos^2(18)+cos^2(12)+2cos12sin18+sin^2(18)=1+2sin12+cos18+2cis12sin18=2+2sin30=3

Բ) (cos20-cos40)^2+(sin20+sin40)^2=cos^2(20)-2cos20cos40+cos^2(40)+sin^2(20)+2sin20sin40+sin^2(40)=2-2cos20cos40+2sin20sin40=2-2cos(20+40)=1

Ա) cos23-(sin22/cos22)*sin23=cos23-(sin22*sin23/cos22)=(cos23*cos22-sin22*sin23)/cos22=cos(23+22)/cos22=cos45/cos22; sin8+(sin22/cos22)*cos8=sin8+((sin22*cos8)/cos22)=(sin8*cos22+sin22*cos8)/cos22=sin80/cos22=0.5/0.25=2; √0.5/0.5=√2

Ա) (sin x cos y+cos x sin y)(sin x cos y-cos x sin y)=sin^2 x cos^2 y-cos^2 x sin^2 y=sin^2 x(1-sin^2 y)-(1-sin^2 x)sin^2 y=sin^2 x-sin^2 y

Բ) (sin x cos y+cos x sin y)(sin x cos-cos x sin y)=sin^2 x cos^2 y-cos^2 x sin^2 y=cos^2 x(1-cos^2 y)-(1-cos^2 x)cos^2 x-cos^ y

Ա) -2

Բ) 4

Ա) -1

Բ) -0.93

Ա) ((5m-10/m^3-8)-(m+2/m^2+2m+4))*(2m^2+4m+8/m-3)==-m+/m^2+2m+4*2m^2+4+8/m-3=(-m+3)(2m^2+4m+8)/(m^2+2m+4)(m-3)=-(2m^2+4m+8)/m^2+2m+4=-2(m^2+2m+4)/m^2+2m+4=-2