bonsoir
O=(x+1)(7-x) - (-1-x)(x+7)
O=(x+1)(7-x) - (-(1+x))(x+7)
O=(x+1)[(7-x)+(x+7)]
O=(x+1)(7-x+x+7)
O= 14(x+1)
P=X^2+6x+9-(2x-3)(x+3)
P=(x+3)^2-(2x-3)(x+3)
P=(x+3)[(x+3)-(2x-3)]
P=(x+3)(x+3-2x+3)
P=(x+3)(-x+6)
H=(3x-4)(x+5)-(-6x+1)(x+5)
H=(x+5)[(3x-4)-(-6x+1)]
H=(x+5)(3x-4+6x-1)
H=(x+5)(9x-5)
E=(8x-1)^2-(5x+2)(8x-1)
E=(8x-1)[(8x-1)-(5x+2)]
E=(8x-1)(8x-1-5x-2)
E=(8x-1)(3x-3)
E=3(8x-1)(x-1)