Вычислить lim (1-sin x/2) / cosx/2 (cosx/4-sinx/4) … x стремится к pi

lim (1-sin x/2) / (cosx/2 (cosx/4-sinx/4)=lim (cos^2 (x/4) -2sin (x/4) cos (x/4)+sin^2 (x/4) / (cosx/2 (cosx/4-sinx/4)=lim (cos (x/4) -sin (x/4) ^2/ (cosx/2 (cosx/4-sinx/4)=lim (cos (x/4) -sin (x/4) / (cosx/2)=lim (cos (x/4) -sin (x/4) / (cos^2 (x/4) -sin^2 (x/4)=lim (cos (x/4) -sin (x/4) / (cos (x/4) -sin (x/4) (cos (x/4)+sin (x/4)=lim (1/ (cos (x/4)+sin (x/4)=1/ (K (2) /2+K (2) /2)=1/K (2)=K (2) /2