Set theory symbols > symmetric difference:

Symbol: A ∆ B

Symbol Name: symmetric difference

Meaning / definition: objects that belong to A or B but not to their intersection

Example: A = {3,9,14},

B = {1,2,3},

A ∆ B = {1,2,9,14}

B = {1,2,3},

A ∆ B = {1,2,9,14}