Biết \(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWaa8qCaeaada % qadaqaaiaaikdacaWG4bGaeyOeI0IaaGymaaGaayjkaiaawMcaaiaa % bsgacaWG4baaleaacaWGHbaabaGaamOyaaqdcqGHRiI8aOGaeyypa0 % JaaGymaaaa!42C3! \int\limits_a^b {\left( {2x - 1} \right){\rm{d}}x} = 1\) . Khẳng định nào sau đây là đúng?

Ta có \(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWaa8qCaeaada % qadaqaaiaaikdacaWG4bGaeyOeI0IaaGymaaGaayjkaiaawMcaaiaa % bsgacaWG4baaleaacaWGHbaabaGaamOyaaqdcqGHRiI8aOGaeyypa0 % ZaaqGaaeaadaqadaqaaiaadIhadaahaaWcbeqaaiaaikdaaaGccqGH % sislcaWG4baacaGLOaGaayzkaaaacaGLiWoadaqhaaWcbaGaamyyaa % qaaiaadkgaaaaaaa!4AFB! \int\limits_a^b {\left( {2x - 1} \right){\rm{d}}x} = \left. {\left( {{x^2} - x} \right)} \right|_a^b\)\(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaeyypa0Jaam % OyamaaCaaaleqabaGaaGOmaaaakiabgkHiTiaadkgacqGHsisldaqa % daqaaiaadggadaahaaWcbeqaaiaaikdaaaGccqGHsislcaWGHbaaca % GLOaGaayzkaaaaaa!40CA! = {b^2} - b - \left( {{a^2} - a} \right)\)

Mà \(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWaa8qCaeaada % qadaqaaiaaikdacaWG4bGaeyOeI0IaaGymaaGaayjkaiaawMcaaiaa % bsgacaWG4baaleaacaWGHbaabaGaamOyaaqdcqGHRiI8aOGaeyypa0 % JaaGymaaaa!42C3! \int\limits_a^b {\left( {2x - 1} \right){\rm{d}}x} = 1\)\(% MathType!MTEF!2!1!+- % feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaeyi1HSTaam % OyamaaCaaaleqabaGaaGOmaaaakiabgkHiTiaadkgacqGHsislcaWG % HbWaaWbaaSqabeaacaaIYaaaaOGaey4kaSIaamyyaiabg2da9iaaig % daaaa!424D! \Leftrightarrow {b^2} - b - {a^2} + a = 1\)\(% MathType!MTEF!2!1!+- % feaahqart1ev3aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaeyi1HSTaam % OyamaaCaaaleqabaGaaGOmaaaakiabgkHiTiaadggadaahaaWcbeqa % aiaaikdaaaGccqGH9aqpcaWGIbGaeyOeI0IaamyyaiabgUcaRiaaig % daaaa!424C! \Leftrightarrow {b^2} - {a^2} = b - a + 1\)