Iron Triangle (Vietnam) Iron Triangle (Vietnam) The Iron Triangle (Vietnamese:"Tam Giác Sắt") was a area in the Bình Dương Province of Vietnam, so named due to it being a stronghold of Viet Minh activity during the war. The region was under control of the Viet Minh throughout the French war in Vietnam and continued to be so throughout the phase of American involvement in the Vietnam War, despite concerted efforts on the part of US and South Vietnamese forces to destabilize the region as a power base for their enemy, the communist North Vietnamese–sponsored and–directed South Vietnamese insurgent movement, the National Liberation Front
Conway triangle notation Conway triangle notation In geometry, the Conway triangle notation, named after John Horton Conway, allows trigonometric functions of a triangle to be managed algebraically. Given a reference triangle whose sides are "a", "b" and "c" and whose corresponding internal angles are "A", "B", and "C" then the Conway triangle notation is simply represented as follows: where "S" = 2 × area of reference triangle and in particular Furthermore the convention uses a shorthand notation for formula_14 and formula_15 Hence: Some important identities: where "R" is the circumradius and "abc" = 2"SR" and where "r" is the incenter, formula_22 and formula_23