Question

Which expression is equivalent to

(sin(θ)+cos(θ))^2?

Answer 1

$(sin\varTheta +cos\varTheta)^2 =\\ = sin^2\varTheta +2sin\varTheta*cos\varTheta +cos^2\varTheta=\\ = sin^2\varTheta+cos^2\varTheta +sin2\varTheta = \\ =1 + sin2\varTheta$

answer: $1 + sin2\varTheta$