from math import log q=int(input()) for tests in range(q): a,b,t=map(float,input().split()) # n**a * log(n)**b = t if a==0: print(2.718281828459045**(t**(1/b))) continue MAX = 10 MIN = 0 while MAX-MIN>10**(-9): mid=(MAX+MIN)/2 if (mid ** a) *(log(mid)**b)>=t: MAX=mid else: MIN=mid print((MAX+MIN)/2)