1{56-x-x²≥0 (1){x²-49≠0 (2)(1) x²+x-56≤0x1+x2=-1 u x1*x2=-56x1=-8 U x2=7-8≤x≤7(2)(x-7)(x+7)≠0x≠7 U x≠-7x∈[-8;-7) U (-7;7)2a1=2x-1 a2=x+3 a3=x+15q=a2/a1=a3/a2(x+3)/(2x-1)=(x+15)/(x+3)(x+3)²=(2x-1)(x+15)x²+6x+9-2x²-30x+x+15=0-x²-23x+24=0x²+23x-24=0x1+x2=-23 U x1*x2=-24x1=-24a1=-49 a2=-21 a3=-9x2=1a1=1 a2=4 a3=16