1 + sinx / 1-sinx é igual a ??

#(1+sinx)/(1-sinx )#

#=> ((1+sinx)(1+sinx))/((1-sinx )(1+sinx))# #["multiply and divide by "1+sinx]#

#=>(1+sinx)^2/(1-sin^2x )# #color(white)(wwwwwwwwwww# #[(a+b)(a-b) = a^2-b^2]#

#=>(1+sinx)^2/(cos^2x )# #color(white)(wwwwwwwwwww# #[sin^2x+cos^2x=1]#

#=>[(1+sinx)/(cosx )]^2#

#=>[secx +tanx]^2#