...from what i see the blue is actually fading to white, this can be achieved by a couple of methods...
...draw a triangle with the star tool, reduce sides to three, remove the base line by selecting with the white arrow (direct select tool), hit delete so you only have two sides...
...adjust stroke weight and expand fill and stroke (object expand) and then add a blue to white gradient at 90 degrees to the what was a stroke, remove any fill from the inside of the triangle...
...copy across once, then press command + D to duplicate another two times the same distance...
...the other method is to use an opacity mask on just a stroked triangle...
Andrew
