X= (0,25)^0,25 = (25/100)^(25/100) = (1/4)^(1/4) = (4)^(-1/4) = (2²)^(-1/4) = (2)^(-2/4) = 2^(-1/2)
y= (16)^(- 0,125) = (2^4)^(-125/1000) = (2^4)^(-1/8) = (2)^(-4/8) = 2^(-1/2)
x = y = 2^(-1/2)
x = y = 2^(-1/2) = (1/2)^(1/2) = √(1/2) = √1/√2 = 1/√2 = (1 x √2)/(√2 x √2) = √2/2
x = y = √2/2