If `(cos(x-y))/(cos(x+y))=m/n ,` then write the value of `tan x tanydot`

Explanation

We have,

`cos(x−y)/cos(x+y)=m/n`

`=>(cosxcosy+sinxsiny)/(cosxcosy−sinxsiny)=m/n`

`=>((cosxcosy)/(cosxcosy)+(sinxsiny)/(cosxcosy))/((cosxcosy)/(cosxcosy)−(sinxsiny)/(cosxcosy))=m/n`

`=>(1+tanxtany)/(1−tanxtany)=m/n`

`=>n+ntanxtany=m−mtanxtany`

`=>tanxtany(n+m)=m−n`

`=>tanxtany=(m−n)/(m+n)`