( x+y ) 2 = x 2 +2xy+ y 2 MathType@MTEF@5@5@+=feaaguart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLnhiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=xfr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWaaeWaaeaacaWG4bGaey4kaSIaamyEaaGaayjkaiaawMcaamaaCaaaleqabaGaaGOmaaaakiabg2da9iaadIhadaahaaWcbeqaaiaaikdaaaGccqGHRaWkcaaIYaGaamiEaiaadMhacqGHRaWkcaWG5bWaaWbaaSqabeaacaaIYaaaaaaa@44A4@