解方程,2倍x的平方减一等于根号三x,有一位同学解答如下
\u5316\u7b80\uff1a\u6839\u53f748\u51cf\u6839\u53f73\u662f\u591a\u5c11 \u8ba1\u7b97\uff1a\u6839\u53f7\uff08\u6839\u53f73-2\uff09\u7684\u5e73\u65b9+\u6839\u53f73\u7b49\u4e8e\u591a\u5c11 \u65b9\u7a0b\uff1a\u6839\u53f71-x=2\u7684\u6839\u662f\u591a\u5c11\u6839\u53f748\u51cf\u6839\u53f73=4\u6839\u53f73-\u6839\u53f73=3\u6839\u53f73
\u6839\u53f7\uff08\u6839\u53f73-2\uff09\u7684\u5e73\u65b9+\u6839\u53f73
=2-\u6839\u53f73+\u6839\u53f73
=2
\u6839\u53f71-x=2
1-x=4
x=1-4
x=-3
\u539f\u65b9\u7a0b\u56e0\u5f0f\u5206\u89e3\u5f97\uff1a
(x- \u6839\u53f73)[x-(2-\u6839\u53f73)]=0
\u89e3\u5f97\uff1ax=\u6839\u53f73\u6216x=2-\u6839\u53f73
2x²-√3x-1=0
x=[√3±√(3+8)]/4=(√3±√11)/4
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绛旓細鏍瑰彿-1绛変簬1銆傞潪璐熸у湪瀹炴暟鑼冨洿鍐咃紝锛1锛夊伓娆℃牴鍙蜂笅涓嶈兘涓鸿礋鏁帮紝鍏惰繍绠楃粨鏋滀篃涓嶄负璐熴傦紙2锛夊娆℃牴鍙蜂笅鍙互涓鸿礋鏁般備笉闄愪簬瀹炴暟锛屽嵆鑰冭檻铏氭暟鏃讹紝鍋舵鏍瑰彿涓嬪彲浠ヤ负璐熸暟锛屽埄鐢ㄣ恑=鈭-1銆戝嵆鍙
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