2 / 2/x\\ |-1 + tanh |-|| 2/x\ \ \2// -2 + 2*tanh |-| - ---------------- \2/ 2/x\ tanh |-| \2/ ---------------------------------- 4
/ 2 \ | / 2/x\\ / 2/x\\| | |-1 + tanh |-|| 2*|-1 + tanh |-||| / 2/x\\ | /x\ \ \2// \ \2//| |-1 + tanh |-||*|- 2*tanh|-| - ---------------- + -----------------| \ \2// | \2/ 3/x\ /x\ | | tanh |-| tanh|-| | \ \2/ \2/ / -------------------------------------------------------------------- 4