How to alter the value of a signal via poti?

Hi.

poti1 should accelarate both motors simultaneously.

poti2 should alter the value given by poti1, so that when i turn the poti left the left motor gets the max value determined by poti1 and the right motor should get a decreasing value from the max value determined by poti1.

Does anyone know what i have to do in order to achieve this? I am sure this is kind of easy but I am pretty new to the Arduino stuff.

#include <Servo.h>
Servo ESC;     // create servo object to control the ESC
Servo ESC2;
int potValue;  // value from the analog pin
void setup() {
  // Attach the ESC on pin 9, ESC2 on pin 10
  ESC.attach(9,1000,2000); // (pin, min pulse width, max pulse width in microseconds) 
  ESC2.attach(10,1000,2000); // (pin, min pulse width, max pulse width in microseconds) 
}
void loop() {
  potValue = analogRead(A0);   // reads value of the potentiometer (value between 0 and 1023)
  potValue = map(potValue, 0, 1023, 0, 180);   // scale to set max speed (value between 0 and 180)
  ESC.write(potValue);    // Send the signal to the ESC
  ESC2.write(potValue);    // Send the signal to the ESC2
}

You need to read that second pot and do the math You told us.

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