1sin40−√3cos40 düzenleyip hertarafı 12 ile çarpalım
12.cos40−√32.sin4012sin40.cos40
---------------------------------------------------------------------------------
---------------------------------------------------------------------------------
Kural_;
2sinx.cosx=sin2x
sinx.cosx=sin2x2
sin(30−40)=−sin(40−30)=sin30.cos40−sin40.cos30
---------------------------------------------------------------------------------
---------------------------------------------------------------------------------
sin80=cos10
12.cos40−√32.sin4012sin40.cos40=−sin1014.sin80=−4.tan10