设.x1,x2是方程x的平方减x减2015等于0的两实数跟,则x1的三次方加2016x2减201 设x1,x2是方程x的平方减x减2013等于0的两实数跟,求...
\u8bbex1,x2\u662f\u65b9\u7a0bx\u7684\u5e73\u65b9-x-2015=0\u7684\u4e24\u4e2a\u5b9e\u6570\u6839,\u6c42x1\u7684\u7acb\u65b9 2016x2-2015x1\u548cx2\u662f\u65b9\u7a0bx^2-x-2013=0\u7684\u6839
\u6839\u636e\u97e6\u8fbe\u5b9a\u7406\u6709\uff1ax1+x2=1
x1*x2=-2013
x1^3+2014x2-2013
=(x1+2013)x1+2014x2-2013
=x1^2+2013x1+2014x2-2013
=x1+2013+2013x1+2014x2-2013
=2014(x1+x2)
=2014
所以 x1^3+2016x2-201=x1(x1+2015)+2016x2-201
=x1^2+2015x1+2016x2-201
=x1+2015+2015x1+2016x2-201
=2016(x1+x2)+2015-201
=4031-201
=3830
【若201是2015之误,则=2016 ;若201是2016之误 ,则 =2015】
绛旓細=x1^2+2015x1+2016x2-201 =x1+2015+2015x1+2016x2-201 =2016(x1+x2)+2015-201 =4031-201 =3830 銆愯嫢201鏄2015涔嬭锛屽垯=2016 锛涜嫢201鏄2016涔嬭 锛屽垯 =2015銆
绛旓細瑙o細锛�0�5-锛-4=0鐨勪袱鏍涓篨1鍜 X2 鎵浠1+ X2 =1 X1X2=-4 鎶奨1浠e叆寰锛1�0�5-锛1-4=0 涓よ竟鍚屾椂涔樹互X1寰 X1�0�6-锛1�0�5-4X1=0 X1�0�6=锛1�0...
绛旓細绛旀鏄6 浼熻揪瀹氱悊-a/b=x1+x2=1 x2=1-x1 x1^3+6x2-5=x1^3-6x1+1=x1(x1^2-x1)+x1^2-6x1+1 鍥犱负鐢遍鍙緱x1^2-x1=5 鎵浠ュ師寮忎负5x1+x1^2-6x1+1=5+1=6
绛旓細鍥
绛旓細x1鍜x2鏄柟绋媥^2-x-2013=0鐨勬牴 鏍规嵁闊﹁揪瀹氱悊鏈夛細x1+x2=1 x1*x2=-2013 x1^3+2014x2-2013 =(x1+2013)x1+2014x2-2013 =x1^2+2013x1+2014x2-2013 =x1+2013+2013x1+2014x2-2013 =2014(x1+x2)=2014 鍦ㄥ彸涓婅鐐瑰嚮銆愯瘎浠枫,鐒跺悗灏卞彲浠ラ夋嫨銆愭弧鎰,闂宸茬粡瀹岀編瑙e喅銆戜簡.
绛旓細鍥犱负 x1銆x2 鏄柟绋 x^2-(m-1)x-m=0 鐨勪袱涓疄鏍癸紝鍒 x1+x2= m-1 锛寈1*x2= -m 锛岀敱宸茬煡寰 1/x1+1/x2=(x1+x2)/(x1*x2)=(m-1)/(-m)= -2/3 锛岃В寰 m= 3 銆
绛旓細鑻ユ墍缁鏂圭▼鏄:x鐨勫钩鏂-2(k-1)x+k鐨勫钩鏂=0 鍒:X1鐨勫钩鏂+X2鐨勫钩鏂=(x1+x2)^2-2x1*x2=4(k-1)^2-2k^2=4 (鏍规嵁鐨勬槸浜屾鏂圭▼鏍逛笌绯绘暟鐨勫叧绯)鍗:K(K-4)=0 寰桲=0鎴朘=4(缁忛獙姝d笉鍚堥鎰,鑸嶅幓)涓妤兼濊矾姝g‘,璁$畻閿欒.
绛旓細2015-06-04 璁緓1x2鏄柟绋媥2-x-2015鐨勪袱涓疄鏁版牴,鍒檟1鐨3娆... 98 2014-09-15 璁緓1,x2鏄柟绋媥^2-x-2013=0鐨勪袱涓疄鏁版牴,鍒檟... 65 2015-04-09 璁.x1,x2鏄柟绋媥鐨勫钩鏂瑰噺x鍑2015绛変簬0鐨勪袱瀹炴暟璺,... 35 2015-02-08 璁緓1銆亁2鏄柟绋媥2-x-1=0鐨勪袱涓疄鏁版牴,鍒檟1+x2... 2015-...
绛旓細绛旓細x1鍜寈2鏄柟绋x^2-x-2013=0鐨勬牴 鏍规嵁闊﹁揪瀹氱悊鏈夛細x1+x2=1 x1*x2=-2013 x1^3+2014x2-2013 =(x1+2013)x1+2014x2-2013 =x1^2+2013x1+2014x2-2013 =x1+2013+2013x1+2014x2-2013 =2014(x1+x2)=2014
绛旓細瑙o細鐢遍鎰忓緱锛(x1)²-x1-1=0 鍗筹細(x1)²=x1+1 x1鐨鍥涙鏂+3x2 =[(x1)²]²+3x2 =(x1+1)²+3x2 =(x1)²+2x1+1+3x2 =x1+1+2x1+1+3x2 =3x1+3x2+2 =3(x1+x2)+2 鐢遍煢杈惧畾鐞嗗緱锛歺1+x2=1 鎵浠ワ細鍘熷紡=3*1+2=5 ...