How do you verify #(1+tan x) / (1+cot x) = 2#?

1 Answer
Jun 18, 2015

It is not possible to verify #(1+tan(x))/(1+cot(x)) = 2
because it isn't (in general) true.

Explanation:

As an obvious counter example consider the case when #x=pi/4#.

#color(white)("XXXX")##(1+tan(pi/4))/(1+cot(pi/4))#

#color(white)("XXXX")##color(white)("XXXX")##=(1+1)/(1+1)#

#color(white)("XXXX")##color(white)("XXXX")##= 1#

#color(white)("XXXX")##color(white)("XXXX")##!= 2#

In fact with very little manipulation it is easy to show:
#color(white)("XXXX")##(1+tan(x))/(1+cot(x)) = tan(x)#