Question

1) cos105cos5 + sin105cos85
--------------------------------------------=
sin195cos5 + cos195sin185

2)sin75cos5 - cos75cos85
---------------------------------------=
cos375cos5 - sin15sin365

Answer 1

решение приведено во вложении

153176461f36f46d9d98714f9bb50084.doc

Answer 2

cos105cos5 + sin105cos85          cos105cos5 + sin105cos(90-5)         
--------------------------------------------=    --------------------------------------------------------------=
sin195cos5 + cos195sin185         sin(105+90)cos5 + cos(105+90)(sin180+5)

      cos105cos5 + sin105sin5
= -------------------------------------------- =1
    cos105cos5 + (-sin105)(-sin5)

2)sin75cos5 - cos75cos85       sin(90-15)cos5 - cos(90-15)cos(90-5)    
--------------------------------------- = -------------------------------------------------------- =
cos375cos5 - sin15sin365       cos(360+15)cos5 - sin15sin(360+5)

     cos15cos5 - sin15sin5
= ----------------------------------- =1
    cos15cos5 - sin15sin5
 

153176461f36f46d9d98714f9bb50084.doc