Jawabanmu

2014-08-25T18:19:09+07:00
(3a²).(a²) + (3a²).(-b²) + (b²).(a²) + (b²).(-b²) = 3a^4 - 3a²b² + a²b² - b^4 = 3a^4 - 2a²b² - b^4