If cos(x)+sin(x)=2sin(θ)\cos(x) + \sin(x) = \sqrt{2}\sin(\theta)cos(x)+sin(x)=2sin(θ), which of the following is a valid expression for θ\thetaθ?
θ=x+π/4\theta = x + \pi/4θ=x+π/4
θ=x−π/4\theta = x - \pi/4θ=x−π/4
θ=π/4−x\theta = \pi/4 - xθ=π/4−x
θ=x+π/2\theta = x + \pi/2θ=x+π/2