Répondre :
5(x-1)(x+1)-(x+3/4)(x-1)(2x+1) =0
(x-1)[5x+5-(x+0,75)(2x+1)] =0
(x-1)[5x+5-2x carré -x-1,5x-0,75] =0
(x-1)(5x-2x carré-2,5x+4,25) =0
(x-1)(2xcarré+2,5x+4,25) =0
(x-1)[5x+5-(x+0,75)(2x+1)] =0
(x-1)[5x+5-2x carré -x-1,5x-0,75] =0
(x-1)(5x-2x carré-2,5x+4,25) =0
(x-1)(2xcarré+2,5x+4,25) =0