Which of the following are equivalent to cos4(θ)−sin4(θ)cos^4(\theta) - sin^4(\theta)cos4(θ)−sin4(θ)?
cos(2θ)cos(2\theta)cos(2θ)
cos2(θ)−sin2(θ)cos^2(\theta) - sin^2(\theta)cos2(θ)−sin2(θ)
2cos2(θ)−12cos^2(\theta) - 12cos2(θ)−1
1−2sin2(θ)1 - 2sin^2(\theta)1−2sin2(θ)