2sinxcosx-1+sinx-cosx=0
(sinx-cosx)-(sin²x+cos²x-2sinxcosx)=0
(sinx-cosx)-(sinx-cosx)²=0
(sinx-cosx)(1-(sinx-cosx))=0
(sinx-cosx)=0⇒sinx=cosx⇒x=π/4+πn
(sinx-cosx)=1
2sinx/2cosx/2-cos²x/2+sin²x/2-sin²x/2-cos²x/2=0
2sinx/2cosx/2-2cos²x/2=0
sinx/2cosx/2-cos²x/2=0
cosx/2(sinx/2-cosx/2)=0
cosx/2=0⇒x/2=π/2+πn⇒x=π+2πn
(sinx/2-cosx/2)=0⇒sinx/2=cosx/2⇒x/2=π/4+πn⇒x=π/2+2πn