Réponse :
I = 2(y^2 - 2*y*5 + 5^2) - 12 + 10y
= 2(y^2-10y+25)-12+10y
= 2y^2-20y+50-13+10y
= 2y^2 -10y +37
J = (1+9x)(1-9x)+(3x+7)^2
= 1^2 - (9x)^2 + (9x^2 + 42x + 49)
= 1-9x^2+9x^2+42x+49
= 92
K= 6x^2 -18 -(x-4)^2
= 6x^2 -18 - (x^2 - 8x +16)
= 6x^2 -x^2 + 8x -18-16
= 5x^2 +8x -34
