#include <iostream>
#include <cmath>
#include <cstdio>
using namespace std;

int a, b;
double t;
double f(double x) {
  return pow(x, a) * pow(log(x), b) - t;
}

double fn(double x) {
  return a * pow(x, a - 1) * pow(log(x), b) + b * pow(x, a - 1) * pow(log(x), b - 1);
}
int main() {
  int T;
  scanf("%d", &T);
  while(T--) {
    scanf("%d %d %lf", &a, &b, &t);
    if(a == 0) {
      printf("%.11f\n", exp(pow(t, 1.0 / b)));
    }else if(b == 0) {
      printf("%.11f\n", pow(t, 1.0 / a));
    }else{
      double x = (pow(t, 1.0 / b)); // 初期値
      for(int i = 0; i < 12; i++) {
        double nx = x - f(x) / fn(x);
        x = nx;
      }
      printf("%.11f\n", x);
    }
  }
}