解:(﹣2xm+1y2n﹣1)•(5xnym)=﹣10xm+n+1ym+2n﹣1=﹣10x4y4,
可得m+n+1=4,m+2n﹣1=4,
解得:m=1,n=2,
则﹣2m2n(﹣
如图所示,一束光线与水平面成45°角,从空气斜射入水中,由此可以断定,该光线所对应的反射光线与折射光线之间的夹角( )
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