import java.io.*; import java.math.*; import java.util.*; import static java.util.Arrays.*; public class _456 { private static final int mod = (int)1e9+7; final Random random = new Random(0); final IOFast io = new IOFast(); /// MAIN CODE public void run() throws IOException { int TEST_CASE = Integer.parseInt(new String(io.nextLine()).trim()); // int TEST_CASE = 1; while(TEST_CASE-- != 0) { a = io.nextInt(); b = io.nextInt(); double t = io.nextDouble(); if (b == 0) { io.out.printf("%.10f\n", Math.pow(t, 1.0/a)); continue; } if (a == 0) { io.out.printf("%.10f\n", Math.exp(Math.pow(t, 1.0/b))); continue; } // io.out.printf("%.10f\n", solve1(t)); io.out.printf("%.10f\n", solve2(t)); } } double solve1(double t) { double x = 1; for (; ; x *= 2) { if (f(x) >= t) break; } double ans = 0; for (int i = 0; x > 1e-10; i++, x /= 2) { if (f(ans + x) <= t) ans += x; } // dump(f(ans)); // io.out.printf("%.10f\n", ans); return ans; } double solve2(double t) { double x = 2; for (int i = 0; i < 20; i++) { double lx = Math.log(x); double v = pow(x, a - 1) * pow(lx, b - 1); double f1 = v * x * lx - t; double f2 = v * (a * lx + b); // dump(x, f1, f2); x -= f1 / f2; } return x; } int a, b; double f(double x) { // return Math.pow(x, a) * Math.pow(Math.log(x), b); return pow(x, a) * pow(Math.log(x), b); } double pow(double x, int a) { double y = 1; for (int i = 0; i < a; i++) y *= x; return y; } // static long powmod(double n, int r) { // long res = 1; // for(; r != 0; r >>>= 1, n = n * n) { // if((r&1) == 1) { // res = res * n; // if(res >= m) { // res %= m; // } // } // } // return res; // } /// TEMPLATE static int gcd(int n, int r) { return r == 0 ? n : gcd(r, n%r); } static long gcd(long n, long r) { return r == 0 ? n : gcd(r, n%r); } static void swap(T[] x, int i, int j) { T t = x[i]; x[i] = x[j]; x[j] = t; } static void swap(int[] x, int i, int j) { int t = x[i]; x[i] = x[j]; x[j] = t; } void printArrayLn(int[] xs) { for(int i = 0; i < xs.length; i++) io.out.print(xs[i] + (i==xs.length-1?"\n":" ")); } void printArrayLn(long[] xs) { for(int i = 0; i < xs.length; i++) io.out.print(xs[i] + (i==xs.length-1?"\n":" ")); } static void dump(Object... o) { System.err.println(Arrays.deepToString(o)); } void main() throws IOException { // IOFast.setFileIO("rle-size.in", "rle-size.out"); try { run(); } catch (EndOfFileRuntimeException e) { } io.out.flush(); } public static void main(String[] args) throws IOException { new _456().main(); } static class EndOfFileRuntimeException extends RuntimeException { private static final long serialVersionUID = -8565341110209207657L; } static public class IOFast { private BufferedReader in = new BufferedReader(new InputStreamReader(System.in)); private PrintWriter out = new PrintWriter(System.out); void setFileIn(String ins) throws IOException { in.close(); in = new BufferedReader(new FileReader(ins)); } void setFileOut(String outs) throws IOException { out.flush(); out.close(); out = new PrintWriter(new FileWriter(outs)); } void setFileIO(String ins, String outs) throws IOException { setFileIn(ins); setFileOut(outs); } private static int pos, readLen; private static final char[] buffer = new char[1024 * 8]; private static char[] str = new char[500*8*2]; private static boolean[] isDigit = new boolean[256]; private static boolean[] isSpace = new boolean[256]; private static boolean[] isLineSep = new boolean[256]; static { for(int i = 0; i < 10; i++) { isDigit['0' + i] = true; } isDigit['-'] = true; isSpace[' '] = isSpace['\r'] = isSpace['\n'] = isSpace['\t'] = true; isLineSep['\r'] = isLineSep['\n'] = true; } public int read() throws IOException { if(pos >= readLen) { pos = 0; readLen = in.read(buffer); if(readLen <= 0) { throw new EndOfFileRuntimeException(); } } return buffer[pos++]; } public int nextInt() throws IOException { int len = 0; str[len++] = nextChar(); len = reads(len, isSpace); int i = 0; int ret = 0; if(str[0] == '-') { i = 1; } for(; i < len; i++) ret = ret * 10 + str[i] - '0'; if(str[0] == '-') { ret = -ret; } return ret; } public long nextLong() throws IOException { int len = 0; str[len++] = nextChar(); len = reads(len, isSpace); int i = 0; long ret = 0; if(str[0] == '-') { i = 1; } for(; i < len; i++) ret = ret * 10 + str[i] - '0'; if(str[0] == '-') { ret = -ret; } return ret; } public char nextChar() throws IOException { while(true) { final int c = read(); if(!isSpace[c]) { return (char)c; } } } int reads(int len, boolean[] accept) throws IOException { try { while(true) { final int c = read(); if(accept[c]) { break; } if(str.length == len) { char[] rep = new char[str.length * 3 / 2]; System.arraycopy(str, 0, rep, 0, str.length); str = rep; } str[len++] = (char)c; } } catch(EndOfFileRuntimeException e) { ; } return len; } int reads(char[] cs, int len, boolean[] accept) throws IOException { try { while(true) { final int c = read(); if(accept[c]) { break; } cs[len++] = (char)c; } } catch(EndOfFileRuntimeException e) { ; } return len; } public char[] nextLine() throws IOException { int len = 0; str[len++] = nextChar(); len = reads(len, isLineSep); try { if(str[len-1] == '\r') { len--; read(); } } catch(EndOfFileRuntimeException e) { ; } return Arrays.copyOf(str, len); } public String nextString() throws IOException { return new String(next()); } public char[] next() throws IOException { int len = 0; str[len++] = nextChar(); len = reads(len, isSpace); return Arrays.copyOf(str, len); } // public int next(char[] cs) throws IOException { int len = 0; cs[len++] = nextChar(); len = reads(cs, len, isSpace); return len; } public double nextDouble() throws IOException { return Double.parseDouble(nextString()); } public long[] nextLongArray(final int n) throws IOException { final long[] res = new long[n]; for(int i = 0; i < n; i++) { res[i] = nextLong(); } return res; } public int[] nextIntArray(final int n) throws IOException { final int[] res = new int[n]; for(int i = 0; i < n; i++) { res[i] = nextInt(); } return res; } public int[][] nextIntArray2D(final int n, final int k) throws IOException { final int[][] res = new int[n][]; for(int i = 0; i < n; i++) { res[i] = nextIntArray(k); } return res; } public int[][] nextIntArray2DWithIndex(final int n, final int k) throws IOException { final int[][] res = new int[n][k+1]; for(int i = 0; i < n; i++) { for(int j = 0; j < k; j++) { res[i][j] = nextInt(); } res[i][k] = i; } return res; } public double[] nextDoubleArray(final int n) throws IOException { final double[] res = new double[n]; for(int i = 0; i < n; i++) { res[i] = nextDouble(); } return res; } } }