| bonjour MATHEMATIQUES
A=(2x+5)( 20x + 1) B = (4)
C = (-x+3)(-x+17)

bonjour
A = 2 x * 20 x + 2 x * 1 + 5 * 20 x + 5 *1
= 40 x² + 2 x + 100 x + 5
= 40 x² + 102 x + 5
B = 4 x * 5 x + 4 x * 4 - 7 * 5 x - 7 * 4
= 20 x² + 16 x - 35 x - 28
= 20 x² - 29 x - 28
C = - x * - x - x * 17 + 3 * - x + 3 * 17
= x² - 17 x - 3 x + 51
= x² - 20 x + 51
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