FALSE sin(α^2) + cos(α^2) = 1 is FALSE. It's attempting to trick you by resembling a different identity of: sin(α)^2 + cos(α)^2 = 1 which is quite true. To illustrate, you can have the expression x = α^2 and substitute it into the expression, getting sin(x) + cos(x) = 1 which you should recognize as being false.