.若方程:x^2+2(m+1)x+3m^2+4mn+4n^2+2=0有实数根,则实数m=?;且实数n=?

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.若方程:x^2+2(m+1)x+3m^2+4mn+4n^2+2=0有实数根,则实数m=?;且实数n=?.若方程:x^2+2(m+1)x+3m^2+4mn+4n^2+2=0有实数根,则实数m=?;且实

.若方程:x^2+2(m+1)x+3m^2+4mn+4n^2+2=0有实数根,则实数m=?;且实数n=?
.若方程:x^2+2(m+1)x+3m^2+4mn+4n^2+2=0有实数根,则实数m=?;且实数n=?

.若方程:x^2+2(m+1)x+3m^2+4mn+4n^2+2=0有实数根,则实数m=?;且实数n=?
因为关于X的一元两次方程x^2+2(m+1)x+(3m^2+4mn+4n^2+2)=0有实根
所以△=〔2(m+1)〕^2-4(3m^2+4mn+4n^2+2)≥0
4m^2+8m+4-(12 m^2+16mn+16n^2+8) ≥0
4m^2+8m+4-12 m^2-16mn-16n^2-8≥0
合并同类项,整理得
2m^2+4mn-2m+4n^2+1≤0
(m+2n) ^2+(m-1) ^2≤0
m=1
n=-1/2

有实数根
△>=0
4(m+1)²-4(3m²+4mn+4n²+2)>=0
m²+2m+1-3m²-4mn-4n²-2>=0
2m²+4mn+4n²-2m+1<=0
所以(m²-4mn+4n²)+(m²-2m+1)<=0
(m-2n)²+(m-1)²<=0
所以只有m-2n=0,m-1=0
所以
m=1
n=m/2=1/2