Mathematical problem of senior one: it is known that y = f (x) is an increasing function in the domain (- 1,1) and f (1 + a) is less than f (A2-1) (A2 represents the square of a, then the range of a is

Mathematical problem of senior one: it is known that y = f (x) is an increasing function in the domain (- 1,1) and f (1 + a) is less than f (A2-1) (A2 represents the square of a, then the range of a is

f(1+a)