先化简,后求值:m²+n²+mn/m²-n²,其中m:n=7:8
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![先化简,后求值:m²+n²+mn/m²-n²,其中m:n=7:8](/uploads/image/z/1012572-36-2.jpg?t=%E5%85%88%E5%8C%96%E7%AE%80%2C%E5%90%8E%E6%B1%82%E5%80%BC%3Am%26%23178%3B%2Bn%26%23178%3B%2Bmn%2Fm%26%23178%3B-n%26%23178%3B%2C%E5%85%B6%E4%B8%ADm%3An%3D7%3A8)
先化简,后求值:m²+n²+mn/m²-n²,其中m:n=7:8
先化简,后求值:m²+n²+mn/m²-n²,其中m:n=7:8
先化简,后求值:m²+n²+mn/m²-n²,其中m:n=7:8
(m²+n²+mn)/(m²-n²) 分子分母同除以n²
=[(m/n)²+1+m/n]/[(m/n)²-1]
=[(7/8)²+1+7/8]/[(7/8)²-1]
=169/64/(-15/64)
=-169/15