double tensionEYE3max = 3.5;
double Bchoisi = 2.0;
double tensionEYE3atraiter=3.5;

void setup() {
  Serial.begin(115200);
  double tensionVoulueEnSortie = tensionEYE3max - pow(pow(tensionEYE3max, Bchoisi) - pow(tensionEYE3atraiter, Bchoisi), 1.0 / Bchoisi);
  Serial.println(tensionVoulueEnSortie);
}

void loop() {}