// もちろん落ちるけど
#include <bits/stdc++.h>
using namespace std;
typedef double Double;
#define double long double
const double EPS = 1e-12;

double a,b,t;

double f(double x){
	return a * x + b * log(x) - log(t);
}
double fd(double x){
	return a + b / x;
}


double initv = 0.0001;
double solve(){
	if( b == 0 ){
		return pow(t,(double)1./a);
	}
	double x = initv;
	for(int i = 0 ; i < 16 ; i++){ 
		x = x - f(x) / fd(x);

	}
	return exp(x);
}





int main(){
	int n;
	cin >> n;
	for(int i = 0 ; i < n ; i++){
		
		scanf("%Lf%Lf%Lf",&a,&b,&t);
		Double ans;
		while(1){
			ans = (Double)solve();
			if( isnan((double)ans)){
				initv = (rand() % 10000+1)/1000.;
			}else break;
		}

		printf("%.12lf\n",ans);
		//cout << solve(a,b,t) << endl;
	}
}