Is sinx cosx ever equal to 1?

From Pythagorean Identities sin^2 x + cos^2 x = 1

and from that identities we can have sinx + cosx = 1, taking sinx = 1 - cosx and substitute in the equation

sinx + cosx = 1

(1 - cosx) + cosx = 1

Remove the parenthesis

1 - cosx + cosx = 1

cancel cosx

1=1