x = float(input("x: "))
if x <= 0:
print("f(", x, ") = ", pow(x, 2), sep="")
elif x >= 1.5:
print("f(", x, ") = ", pow(2*x - 3, 0.5), sep="")
else:
print("f(", x, ") = ", 1, sep="")
