<span>to answer the question above, take the LHS. [(tan x - 1) / (tan x + 1)] =
Remember that tan x = 1 / cot x. {[(1 / cot x) - 1] / [(1 / cot x) + 1]} =
The LCD is cot x. Multiply as needed to get the common denominator for all terms. {[(1 / cot x) - 1(cot x / cot x)] / [(1 / cot x) + 1(cot x / cot x)]} = {[(1 / cot x) - (cot x / cot x)] / [(1 / cot x) + (cot x / cot x)]} =