Sagot :
Bonjour,
(1+4x)²=(8x+1)(2x-3)
1² + 8x + 16x² = 16x² - 24x + 2x - 3
16x² + 8x + 1 = 16x² - 22x - 3
8x+1 = -22x-3
30x+1 = -3
30x = -4
x = -4/30
x = -2/15
:)
(1+4x)²=(8x+1)(2x-3)
(1² + 2*1*4x + 4x²) = (8x*2x + 8x * -3 + 1*2x + -3 *1)
1² + 8x +16x² = 16x² - 24x +2x -3
1 + 8x +16x² = 16x² -22x -3
1 +8x +16x² - 16x² +22x +3 =0
4 + 30x = 0
30x = -4
x = -4/30
x= -2/15