[phpBB Debug] PHP Warning: in file [ROOT]/ext/lmdi/autolinks/event/listener.php on line 237: Undefined array key 9 [phpBB Debug] PHP Warning: in file [ROOT]/ext/lmdi/autolinks/event/listener.php on line 237: Trying to access array offset on value of type null Solve the equation on the interval [0,2). sin 2x= sin x - - Answer Happy