(х+4.9/11)-5.6/11=1.8/11
х+4.9/11=1.8/11+5.6/11
х+4.9/11=6.14/11
х+4.9/11=7.3/11
х=7.3/11-4.9/11
х=(7-4)+(3/11-9/11)
х=3.3-9/11
х=2.11+3-9/11
х=2.5/11
проверяем
(2.5/11+4.9/11)-5.6/11=1.8/11
13.2/9-(7.5/9+у)=3.5/9
7.5/9+у=13.2/9-3.5/9
7.5/9+у=(13-3)+(2/9-5/9)
7.5/9+у=10.2-5/9
7.5/9+у=9.9+2-5/9
7.5/9+у=9.6/9
у=9.6/9-7.5/9
у=2.1/9
проверяем
13.2/9-(7.5/9+2.1/9)=3.5/9
Sin13°cos3°-sin5°sin85°-cos8°cos82°=
sin13°cos3°-sin5°cos(90°-85°)-cos8°sin(90°-82°)=
sin13°cos3°-(2sin5°cos5°+2cos8°sin8°)/2=
sin13°cos3°-(sin10°+sin16°)/2=
sin13°cos3°-(sin(13°-3°)+sin(13°+3°))/2=
sin13°cos3°-(sin13°cos3°-cos13°sin3°+sin13°cos3°+cos13°sin3°)/2=
sin13°cos3°-(2sin13°cos3°)/2=
sin13°cos3°-sin13°cos3°=0
Пожалуйста дай картинку. И тогда я обязательно дам ответ