Normally, "factoring" means "factor into terms having integer coefficients" and, as VonNemo19 said, that cannot be done here.
But if you really want to factor- and aren't concerned about the factors having integer, or even real, coefficients, you can "complete the square":
(Divide the coefficient of x (1) by to (1/2) and square (1/4). Add and subtract that.)
and think of this as a "difference of squares":
Which can be factored as "sum and difference": .