Question

已知函数y=g(x)=sinx+cosx+2sinxcosx

Answer 1

1.y+1=sin^2x+2sinxcosx+cos^2x+sinx+cosx

y=(sinx+cosx)^2+(sinx+cosx)-1

令t=sinx+cosx

y=t^2+t-1 后面的不说啦