f(x) ( /ˌɛf ˈɛks/; Korean: 에프엑스) is a South Korean girl group formed by SM Entertainment in 2009. The name is a play on the mathematical notation for function. The f stands for flower and the x represents the female’s double x chromosome. f(x) strives to be the kind of girl group that can change and adapt to many situations.[citation needed] The group members have also been nicknamed “function girls”. The group made their debut on September 5, 2009 with release of a digital single “La Cha Ta” (stylized as “LA chA TA”). The quintet consists of Victoria, Amber, Luna, Sulli, and Krystal.
VICTORIA
Birth Name: Song Qian
Birthday: February 2, 1987
Position: Leader, Main Dancer, Vocalist
Height: 168 cm
Blood Type: A
Nationality: Chinese
AMBER
Birth Name: Amber Josephine Liu
Birthday: September 18, 1992
Position: Main Rapper, Vocalist
Height: 167 cm
Blood Type: B
Nationality: American-Chinese-Taiwanese
LUNA
Birth Name: Park Sun Young
Birthday: August 12, 1993
Position: Main Vocalist, Lead Dancer
Height: 162 cm
Blood Type: A
Nationality: Korean
SULLI
Birth Name: Choi Jin Ri
Birthday: March 29, 1994
Position: Vocalist, Rapper, Visual
Height: 170 cm
Blood Type: O
Nationality: Korean
KRYSTAL
Birth Name: Krystal Jung/ Jung Soo Jung
Birthday: October 24, 1994
Position: Lead Vocalist, Maknae, Face
Height: 165 cm
Blood Type: A
Nationality: Korean-American