If the straight line y = KX + 1 and the curve X = radical y ^ 2 + 1 have two different intersections, then the value range of K is

If the straight line y = KX + 1 and the curve X = radical y ^ 2 + 1 have two different intersections, then the value range of K is

Curve X = radical y ^ 2 + 1
It is the right branch of the hyperbola x 2 - y 2 = 1
Make up the equations
x²-(kx+1)²=1
(1-k²)x²-2kx-2=0
△=b²-4ac= 4k²+8(1-k²)>0
It is found that K 2 is less than 2
-√2<k<√2