(-b^20)* 81b^8= -81b^28
100c^12y^6 * 16c^2y^4= 1600c^14y^10
25b^4c^3*8b^6c^3=200b^10c^6
НОК(693,1617)=3*3*7*7*11=4851
[√(n+2)*(√(n+2)+√(n-2))]/[√(n+2)*(√(n+2)-√(n-2))] +
+[√(n+2)*(√(n+2)-√(n-2))]/[√(n+2)*(√(n+2)+√(n-2))]=
=(√(n+2)+√(n-2))/(√(n+2)-√(n-2))+(√(n+2)-√(n-2))/(√(n+2)+√(n-2))=
(n+2+2√(n²-2)+n-2+n+2-2√(n²-2)+n-2)/[(√(n+2)+√(n-2))(√(n+2)-√(n-2))]=
=4n/(n+2-n+2)=4n/4=n
√(√2-1)²+2-√2=√2-1+2-√2=1
Cos(2π/3*cosx-4π/3)=1 U cos(2π/3*cosx-4π/3)=-1
2π/3*cosx-4π/3=0 U 2π/3*cosx-4π/3)=π
2π/3*cosx=4π/3 U 2π/3*cosx=4π/3+π=7π/3
cosx=2 нет решения Г сosx=3,5 нет решения