(sinx+tgx) * (cosx+ctgx) = (1+sinx) * (1+cosx)

[Guest]

(sinx+tgx) * (cosx+ctgx) = (1+sinx) * (1+cosx)

[nathi123]

[tex]A = ( sinx+tgx)(cosx+cotgx) = (sinx+\frac{sinx}{cosx})(cosx+\frac{cosx}{sinx})=sinxcosx(1+\frac{1}{cosx})(1+\frac{1}{sinx})\Leftrightarrow[/tex]
[tex]A=\frac{sinxcosx}{sinxcosx}(1+cosx)(1+sinx) =(1+cosx)(1+sinx)[/tex] .