Lim x-0 1-cos x/x решение :(
Lim(x->0)(1-cosx)/(x)=lim(x->0)(2sin^2(x/2))/(2*(x/2))= lim(x->0)(sinx/2)/(x/2)*lim(x->0)(sinx/2)=1*lim(x->0)(sin(x/2))=0