数,∴k
=-1,方程2-kx2+3mx+3-k
=0有两个实数根x1,x2,∴x1+x2=-23-mk=k3-m2=-m,x1x2=(32--kk)
=43
,x1x1-k+x2x2-k=x1-kx2-k,整理得x12+x22=x1x2+k2,∴x1+x22-2x1x2-x1x2=k2,即x1+x22-3x1x2=k2,∴-m2-3×43
=-12,即m2-4
=1,
=m24-1,③Δ=3m2-42-k3-k
=9m2-48
≥0,④把③代入④得9m2-48×m24-1≥0,m2≤4,则m≤2,∴m≤2成立.
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