4) (2x - 1)² - (2x - 1). 6. Factoriser en utilisant les identités remarquables quables. a(x) = 36x² - 84x + 49 b(x) = 25x² + 9 + 30x c(x) = 121 + x² - 22x d(x) = 12x + 9x² + 4 e(x) = 9x² -1 f(x) = 25x² - 64 g(x) = 1 - 49x² h(x) = 2,25x² - 0.36 i(x) = (5x - 1)² = (3 1)² = (3-2x)²​