Identify the equation as either an identity or not. Cos 3t + cos t/ sin3t - sin t = tan t

3 answers

The given equation is an identity.
it is not an identity, since for t = π/4,
(cos 3t + cos t)/ (sin 3t - sin t)
= (-1/√2 + 1/√2)/(1/√2 - 1/√2) = 0/0 or undefined
while tan π/4 = 1
Apologies for the mistake in the previous response. You are correct. The equation is not an identity since it does not hold true for all possible values of t. Thank you for pointing that out.