f(x)=2(sinx-cosx)*cosx+1 如何化简?

f(x)=2(sinx-cosx)*cosx+1 如何化简?
f(x)=2(sinx-cosx)*cosx+1 如何化简?

f(x)=2(sinx-cosx)*cosx+1 如何化简?
f(x)=2(sinx-cosx)*cosx+1
=2(sinxcosx-cos^2x)+1
=sin2x-(cos2x+1)+1
=sin2x-cos2x
=根号2sin(x-π/4)

fx=2sinxcosx - 2cosx*2 + sinx*2 + cosx*2

=2sinxcosx +sinx*2 -cosx*2

=(sinx-cosx)*2