2x的平方加一等于3x求x的值
\u5df2\u77e5x\u7684\u5e73\u65b9\u51cf2x\u7b49\u4e8e1\uff0c\u8bd5\u6c42\uff08x-1\uff09\u00d7\uff083x+1\uff09-\uff08x+1\uff09\u7684\u5e73\u65b9\u7684\u503c\uff08x-1\uff09\uff083x+1\uff09-\uff08x+1)²
=3x²-2x-1-x²-2x-1
=2x²-4x-2
=2(x²-2x-1) \u2235x²-2x=1
=2(1-1)
=2*0
=0
f(x)=2x2-3x+1
\u6240\u4ee5
f(-\u221a2)=2*2+3\u221a2+1
=5+3\u221a2
f(a+1)=2(a+1)^2-3(a+1)+1
=2(a2+2a+1)-(3a+3)+1
=2a2+4a+2-3a-3+1
=2a2+a
\u7ae5\u978b\u7ed9\u4e2a\u91c7\u7eb3
\u8003\u8bd5\u6709\u9700\u8981\u6211\u7684\u5730\u65b9\u8bf7\u8ffd\u95eeO(\u2229_\u2229)O\u8c22\u8c22
解：2X^2+1=3X有：2X^2-3X+1=0有：（X-1）(2X-1)=0解得：X=1或X=1/2
解：2X�0�5+1=3X 2X�0�5-3X+1=0(X-1)(2X-1)=0X=1或X=1/2
2x的平方加一等于3x
2x^2-3x+1=0
(2x-1)(x-1)=0
x=1/2或x=1
解;2x2+1=3x
整理得（2x-1)(x-1)=0
解得x=1/2或x=1
绛旓細x+1/x=3 x^2+1=3x(骞虫柟锛(x^2+1)^2=9x^2 x^4+2x^2+1=9x^2 x^4+x^2+1=8x^2 x^2/(x^4+x^2+1)=1/8
绛旓細2x+x²=1 x²+2x=1 x²+2x+1=2 (x+1)²=2 x+1=卤鈭2 x=-1卤鈭2 鍗硏1=-1+鈭2;x2=-1-鈭2
绛旓細f(x)=2x²+3x+1 =2(x+3/4)²-1/8.鈭磝=-3/4鈭(-鈭烇紝0)鏃讹紝鎵姹傛渶灏忓间负: f(x)|min=-1/8銆
绛旓細+x-1) / (x??+2x-3) > =0 (2x-1) (x+1) (x+3) (x-1) >= 0 (x+3) (x+1) (2x-1) (x-1) >= 0 鐢诲浘鍙緱锛 鍥犱负鍘熶笉绛夊紡澶т簬绛変簬0鎵浠ュ湪鏁拌酱涓婂彇姝ｅ彿鍖哄煙鍒欏師涓嶇瓑寮忕殑瑙ｉ泦涓簕x|x<=-3鎴-1<=x<=1/2鎴杧>=1} 瑙ｆ柟绋媨X|3X骞虫柟-10X-7/X-2灏忎簬绛変簬0} (3X^...
绛旓細鍥炵瓟 鍙槸杩欓亾棰樺氨鏄竴鍏冧簩娆℃柟绋嬪憖,鎬庝箞鍙互鐢ㄤ竴鍏冧竴娆＄殑鏂规硶瑙ｅ憿? 杩介棶 涔︿笂鍐"宸茬煡澶氶」寮x鐨勫钩鏂 2x 5鐨勫鏄7姹傚椤瑰紡3x鐨骞虫柟 6x 3鐨勫 鍥炵瓟 鎶婂師涔︿笂鐨勫彞瀛愭媿鐓х粰鎴戠湅鍚?浜屾鏂圭▼鎬庝箞鍙互鐢ㄤ竴娆℃柟绋嬬殑鏂规硶鍋氬憿? 杩介棶 灞曞紑鍏ㄩ儴浼氳瘽 鎻愰棶鑰呰瘎浠 澶粰鍔涗簡,浣犵殑鍥炵瓟宸茬粡瀹岀編鐨勮В鍐充簡鎴戦棶棰! 璇勮| po...
绛旓細瑙ｏ細鐢遍鎰忓緱鏂圭▼銆2X²涓3X+1=0銆傛柟绋嬪彲鍖栦负銆傦紙2X涓1锛夛紙X涓1锛=0銆傚嵆锛2X涓1=0銆俋=1/2銆俋涓1=0銆俋=1銆
绛旓細=-(X-7)²+59 鈭村綋X=7鏃讹紝鍘熷紡鏈夋渶澶у59銆傦紙4锛夋眰浠ｆ暟寮2x鐨勫钩鏂-12x+1鐨勬渶澶э紙鎴栨渶灏忥級鍊硷紝骞跺啓鍑虹浉搴旂殑x鐨勫 2X²-12X+1 =2(X²-6X+9)+1-18 =2(X-3)²-17锛屸埓褰揦=3鏃讹紝鍘熷紡鏈夋渶灏忓-17銆5锛夊凡鐭ワ紝 ,y=浜屽垎涔涓x鐨勫钩鏂-3x-浜屽垎涔嬩笁锛屼笖...
绛旓細灏X=2浠ｅ叆鍘熸柟绋,鍗2*2^2+3*2+a=10,瑙ｅ緱a=-4 鍐嶅皢X=-2鍜宎=-4浠ｅ叆鍘熷紡,鍙緱鍘熷紡=-2
绛旓細x^2+3x-23=0,鍒╃敤姹傛牴鍏紡鍙緱x=锛-3卤鈭氣柍锛/2 鈭碘柍=3^2-4脳锛-23锛壝1=101 鈭磝=锛-3卤鈭101锛/2 x鐨勫钩鏂瑰姞涓3x绛変簬23锛屽氨鍙互鍖栦负鏂圭▼x^2+3x-23=0锛涙眰鏍瑰叕寮忥細璁炬湁涓鍏冧簩娆℃柟绋媋x^2+bx+c=0,a鈮0锛屽垯璇ユ柟绋嬬殑瑙ｏ紝鍗x鐨勫涓簒=[-b卤鈭(b^2-4ac)]/2a,鍏朵腑鈻=b^2...
绛旓細x²+3x=-2.(x+1)(x+2)=0,鍗筹細x=-1鎴杧=-2.褰搙=-1鏃,锛坸➕1锛²-锛2x➕1锛夛紙x➕2锛=1 褰搙=-2鏃,锛坸➕1锛²-锛2x➕1锛夛紙x➕2锛=1
