используя теорему Виета:х²+px+q=0A) x1+x2=-px1×x2=q-p=(-1)+3=3-1-p=2q=(-1)×3q=-3x²-2x-3=0Проверка:D=(-(-2))²-4×1×(-3)=4+12=16x1=(-(-2)-√16)/2×1=(2-4)/2=-2/2=-1x2=(-(-2)+√16)/2×1=(2+4)/2=6/2=3b) x1+x2=-p-p=1/2+(-3/4)=1/2-3/4=0,5-0,75-p=-0,25-p=-1/4x1×x2=qq=1/2×(-3/4)=0,5×(-0,75)q=-0,375=-(375/1000)=-3/8x²+(1/4)x-(3/8)=0|×88x²+2x-3=0Проверка:D=(-2)²-4×8×(-3)=4+96=100x1=(-2+√100)/2×8=(-2+10)/16=8/16=1/2x2=(-2-√100)/2×8=(-2-10)/16=-12/16=-3/4Ответ:a) x²-2x-3=0b) x²+(1/4)x-(3/8)=0 или 8x²+2x-3=0