Question

For :
tan (Ө - 45 degrees) + tan ( Ө + 45 degrees) = 2 tan2Ө,

how do you apply the identity of :
cot Ө = tan (90 degrees - Ө ) ?
in order to verify the equation.

Answer 1

try expanding them like tan(a-b) = ........... and simplify.........that shud do it

Answer 2

\[\tan(A -B) = \frac{tanA - tanB}{1 + tanA.tanB}\]

\[\tan(A +B) = \frac{tanA + tanB}{1 - tanA.tanB}\]

\[\frac{2tanA}{1 - \tan^2A} = \tan2A\]

Use these identities to verify...