notes our initial reaction here is to do single left rotation let' try that our left rotation has completedand we're stuck in the same situation if we were to do single right rotation in this situationwe would be right back where we started what' causing thisthe answer is that this is result of the right subtree having negative balance in other wordsbecause the right subtree was left heavyour rotation was not sufficient what can we dothe answer is to perform right rotation on the right subtree read that again we will perform right rotation on the right subtree we are not rotating on our current root we are rotating on our right child think of our right subtreeisolated from our main treeand perform right rotation on itbeforec afterb after performing rotation on our right subtreewe have prepared our root to be rotated left here is our tree nowa looks like we're ready for left rotation let' do thatb / voila problem solved lovely professional university