己知实数a,b分别满足a一6a十4=0,b一6a十4=0,且a≠b,求 b/a十a/b的值,
问题描述：
己知实数a,b分别满足a一6a十4=0,b一6a十4=0,且a≠b,求 b/a十a/b的值,
答
a+b=6
ab=4
b/a+a/b
=(a^2+b^2)/(ab)
=(a^2+b^2+2ab)/(ab)-2
=(a+b)^2/(ab)-2
=6^2/4-2
=9-2
=7
选为满意答案哦
以后有不会的还来问我~