(√7-√6)与(√5-2)哪个大,怎样求 -√7与-(√5-1)÷2比较大小的过程
(\u221a7-\u221a6)\u4e0e(\u221a5-2)\u54ea\u4e2a\u5927,\u600e\u6837\u6c42\u6b32\u6bd4\u8f83\u6b642\u6570\u4e4b\u5927\u5c0f,\u53ea\u8981\u6bd4\u8f83\u4ed6\u4eec\u5012\u6570\u7684\u5927\u5c0f.\u5012\u6570\u5927\u7684\u53cd\u800c\u5c0f.\u89e3\u7b54\u8fc7\u7a0b\u5982\u4e0b:
1/(\u221a7-\u221a6)=\u221a7+\u221a6
1/(\u221a5-2)=\u221a5+2
\u56e0\u4e3a\u221a7+\u221a6\u5927\u4e8e\u221a5+2
\u6545(\u221a7-\u221a6)\u5c0f\u4e8e(\u221a5-2)
\u6ce8:2=\u221a4
\u5f00\u5e73\u65b9\u5355\u8d1f\u53f7\u4e0d\u8981\u53bb\u6389
-7\u4e0e-\uff083+\u221a5\uff09/2
\u6240\u4ee5\uff08-3+\u221a5\uff09/2\u5927
\u8fc7\u7a0b\uff1a-\u3010(\u221a5-1)\u00f72\u3011\u7684\u5e73\u65b9=\uff08-3+\u221a5\uff09/2=-\uff083+\u221a5\uff09/2
\u5e0c\u671b\u80fd\u5e2e\u5230\u4f60\uff01
\u4e5f\u5e0c\u671b\u6ca1\u9519\uff01
1/(√7-√6)=√7+√6
1/(√5-2)=√5+2
因为√7+√6大于√5+2
故(√7-√6)小于(√5-2)
注:2=√4
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