已知m,n满足m+n=-2005,mn=7求(m2+2004m+6)(n2+2006n+8)的值
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已知m,n满足m+n=-2005,mn=7求(m2+2004m+6)(n2+2006n+8)的值
已知m,n满足m+n=-2005,mn=7求(m2+2004m+6)(n2+2006n+8)的值
已知m,n满足m+n=-2005,mn=7求(m2+2004m+6)(n2+2006n+8)的值
x^2+2005x+7=0
m,n是以上方程的两个解
m^2+2005m+7=0
n^2+2005n+7=0
(m2+2004m+6)(n2+2006n+8)
=(m^2+2005m+7-m-1)(n^2+2005n+7+n+1)
=(-m-1)(n+1)
=-(m+1)(n+1)
=-(mn+m+n+1)
=-(7-2005+1)
=1997
原式=(m2+2005m+7-m-1)(n2+2005n+7+n+1)
=[m2-m(m+n)+mn-m-1][n2-n(m+n)+mn+n+1]
=(m2-m2-mn+mn-m-1)(n2-mn-n2+mn+n+1)
=(-m-1)(n+1)
=-(m+1)(n+1)
=-(mn+m+n+1)
=-(7-2005+1)
=1997
x^2+2005x+7=0
m,n是以上方程的两个解
m^2+2005m+7=0
n^2+2005n+7=0
(m2+2004m+6)(n2+2006n+8)
=(m^2+2005m+7-m-1)(n^2+2005n+7+n+1)
=(-m-1)(n+1)
=-(m+1)(n+1)原式=(m2+2005m+7-m-1)(n2+2005n+7+...
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x^2+2005x+7=0
m,n是以上方程的两个解
m^2+2005m+7=0
n^2+2005n+7=0
(m2+2004m+6)(n2+2006n+8)
=(m^2+2005m+7-m-1)(n^2+2005n+7+n+1)
=(-m-1)(n+1)
=-(m+1)(n+1)原式=(m2+2005m+7-m-1)(n2+2005n+7+n+1)
=[m2-m(m+n)+mn-m-1][n2-n(m+n)+mn+n+1]
=(m2-m2-mn+mn-m-1)(n2-mn-n2+mn+n+1)
=(-m-1)(n+1)
=-(m+1)(n+1)
=-(mn+m+n+1)
=-(7-2005+1)
=1997
=-(mn+m+n+1)
=-(7-2005+1)
=1997
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