已知实数a,b满足a²+b²+4a-6b+13=0.求(根号b+a)/(根号b-a)的值
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![已知实数a,b满足a²+b²+4a-6b+13=0.求(根号b+a)/(根号b-a)的值](/uploads/image/z/1978797-21-7.jpg?t=%E5%B7%B2%E7%9F%A5%E5%AE%9E%E6%95%B0a%2Cb%E6%BB%A1%E8%B6%B3a%26%23178%3B%2Bb%26%23178%3B%2B4a-6b%2B13%3D0.%E6%B1%82%28%E6%A0%B9%E5%8F%B7b%2Ba%29%2F%28%E6%A0%B9%E5%8F%B7b-a%29%E7%9A%84%E5%80%BC)
已知实数a,b满足a²+b²+4a-6b+13=0.求(根号b+a)/(根号b-a)的值
已知实数a,b满足a²+b²+4a-6b+13=0.求(根号b+a)/(根号b-a)的值
已知实数a,b满足a²+b²+4a-6b+13=0.求(根号b+a)/(根号b-a)的值
a²+b²+4a-6b+13=0
a²+4a+4+b²-6b+9=0
(a+2)²+(b-3)²=0
a+2=0 b-3=0
a=-2 b=3
(根号b+a)/(根号b-a)
=(√3-2)/(√3+2)
=(√3-2)(√3-2)/[(√3+2)(√3-2)]
=(3+4-4√3)/(3-4)
=4√3-7
a²+b²+4a-6b+13=0
(a²+4a+4)+(b²-6b+9)=0
(a+2)²+(b-3)²=0
a+2=0,b-3=0
a=-2,b=3
(根号b+a)/(根号b-a)
=根号1/根号5
=1/5根号5
∵a²+b²+4a-6b+13=0
∴a²+4a+4+b²-6b+9=0
∴(a+2)²+(b-3)²=0
∴a+2=0 b-3=0
∴a=-2 b=3
∴(√b+a)/(√b-a)
=(√3-2)/(√3+2)
=(√3-2)(√3-2)/[(√3+2)(√3-2)]
=(3+4-4√3)/(3-4)
=4√3-7
吧13拆成9+4,凑平方,(a+2)^2+(b-3)^2=0.,相信下面就不用解释了