Répondre :
(x-1)(11-x)+5(x-1)²-[2(x-1)(2x+3)]=0
(x-1)[11-x+5(x-1)-[2(2x+3)]=0
(x-1)[11-x+5x-5-(4x+6)]=0
(x-1)[11-x+5x-5-4x-6]=0
(x-1)(10)=0
Je te laisse conclure
(x-1)(11-x)+5(x-1)²-[2(x-1)(2x+3)]=0
(x-1)[11-x+5(x-1)-[2(2x+3)]=0
(x-1)[11-x+5x-5-(4x+6)]=0
(x-1)[11-x+5x-5-4x-6]=0
(x-1)(10)=0
Je te laisse conclure