Question

1-2sinxcosx-sin^2x=0

Answer 1

cos^2x+sin^2x-2sinxcos-sin^2x=0
cos^2x-2sinxcosx=0
cosx(cosx-2sinx)=0
cosx=0  x=п/2+пn
 
cos-2sinx=0 : cosx
1-2tgx=0
-2tgx=-1
tgx=1/2
x=arctg1/2+пn