y∧4-3y∧3-28y∧2用十字交叉法怎么因式分解
\u56e0\u5f0f\u5206\u89e3\u5341\u5b57\u4ea4\u53c9\u6cd5\u7684\u65b9\u6cd5\u4e00\u3001\u56e0\u5f0f\u5206\u89e3\u7684\u57fa\u672c\u65b9\u6cd5\uff0c
1\u3001\u63d0\u53d6\u516c\u56e0\u5f0f\u6cd5\uff0c
2\u3001\u516c\u5f0f\u6cd5\uff08\u5e73\u65b9\u5dee\u516c\u5f0f\u548c\u5b8c\u5168\u5e73\u65b9\u516c\u5f0f\uff09\u3002
\u5f80\u5f80\u5728\u9898\u76ee\u4e2d\u591a\u5c11\u4f1a\u6d89\u53ca\u4e00\u4e9b\u5176\u4ed6\u7684\u77e5\u8bc6\uff0c\u4f8b\u5982\u914d\u65b9\u6cd5\u548c\u5341\u5b57\u4ea4\u53c9\u6cd5\u7b49\u3002
\u4e8c\u3001\u5341\u5b57\u4ea4\u53c9\u6cd5
1\u3001\u5341\u5b57\u76f8\u4e58\u6cd5\u7684\u65b9\u6cd5\uff1a\u5341\u5b57\u5de6\u8fb9\u76f8\u4e58\u7b49\u4e8e\u4e8c\u6b21\u9879\u7cfb\u6570,\u53f3\u8fb9\u76f8\u4e58\u7b49\u4e8e\u5e38\u6570\u9879,\u4ea4\u53c9\u76f8\u4e58\u518d\u76f8\u52a0\u7b49\u4e8e\u4e00\u6b21\u9879\u7cfb\u6570.
\u5982\u56fe\u6240\u793a\uff1a
2\u3001\u5341\u5b57\u76f8\u4e58\u6cd5\u7684\u7528\u5904\uff1a\uff081\uff09\u7528\u5341\u5b57\u76f8\u4e58\u6cd5\u6765\u5206\u89e3\u56e0\u5f0f.\uff082\uff09\u7528\u5341\u5b57\u76f8\u4e58\u6cd5\u6765\u89e3\u4e00\u5143\u4e8c\u6b21\u65b9\u7a0b.
3\u3001\u5341\u5b57\u76f8\u4e58\u6cd5\u7684\u4f18\u70b9\uff1a\u7528\u5341\u5b57\u76f8\u4e58\u6cd5\u6765\u89e3\u9898\u7684\u901f\u5ea6\u6bd4\u8f83\u5feb,\u80fd\u591f\u8282\u7ea6\u65f6\u95f4,\u800c\u4e14\u8fd0\u7528\u7b97\u91cf\u4e0d\u5927,\u4e0d\u5bb9\u6613\u51fa\u9519.4\u3001\u5341\u5b57\u76f8\u4e58\u6cd5\u7684\u7f3a\u9677\uff1a1\u3001\u6709\u4e9b\u9898\u76ee\u7528\u5341\u5b57\u76f8\u4e58\u6cd5\u6765\u89e3\u6bd4\u8f83\u7b80\u5355,\u4f46\u5e76\u4e0d\u662f\u6bcf\u4e00\u9053\u9898\u7528\u5341\u5b57\u76f8\u4e58\u6cd5\u6765\u89e3\u90fd\u7b80\u5355.2\u3001\u5341\u5b57\u76f8\u4e58\u6cd5\u53ea\u9002\u7528\u4e8e\u4e8c\u6b21\u4e09\u9879\u5f0f\u7c7b\u578b\u7684\u9898\u76ee.3\u3001\u5341\u5b57\u76f8\u4e58\u6cd5\u6bd4\u8f83\u96be\u5b66.5\u3001\u5341\u5b57\u76f8\u4e58\u6cd5\u89e3\u9898\u5b9e\u4f8b\uff1a1)\u3001 \u7528\u5341\u5b57\u76f8\u4e58\u6cd5\u89e3\u4e00\u4e9b\u7b80\u5355\u5e38\u89c1\u7684\u9898\u76ee \u4f8b1\uff1a\u628am²+4m-12\u5206\u89e3\u56e0\u5f0f \u5206\u6790\uff1a\u672c\u9898\u4e2d\u5e38\u6570\u9879-12\u53ef\u4ee5\u5206\u4e3a-1\u00d712,-2\u00d76,-3\u00d74,-4\u00d73,-6\u00d72,-12\u00d71\u5f53-12\u5206\u6210-2\u00d76\u65f6,\u624d\u7b26\u5408\u672c\u9898 \u3002\u56e0\u4e3a \uff1a1 \u2196 \u2197 - 2
\u2197 \u2198
1 6 \u6240\u4ee5m²+4m-12=\uff08m-2\uff09\uff08m+6\uff09 \u4f8b2\uff1a\u628a5x²+6x-8\u5206\u89e3\u56e0\u5f0f \u3002\u5206\u6790\uff1a\u672c\u9898\u4e2d\u76845\u53ef\u5206\u4e3a1\u00d75,-8\u53ef\u5206\u4e3a-1\u00d78,-2\u00d74,-4\u00d72,-8\u00d71.\u5f53\u4e8c\u6b21\u9879\u7cfb\u6570\u5206\u4e3a1\u00d75,\u5e38\u6570\u9879\u5206\u4e3a-4\u00d72\u65f6,\u624d\u7b26\u5408\u672c\u9898 \u3002\u56e0\u4e3a\uff1a 1 \u2196 \u2197 -2
\u2197 \u2198
5 -4
\u6240\u4ee55x²+6x-8=\uff08x+2\uff09\uff085x-4\uff09 \u4f8b3\uff1a\u89e3\u65b9\u7a0bx²-8x+15=0 \u5206\u6790\uff1a\u628ax²-8x+15\u770b\u6210\u5173\u4e8ex\u7684\u4e00\u4e2a\u4e8c\u6b21\u4e09\u9879\u5f0f,\u521915\u53ef\u5206\u62101\u00d715,3\u00d75.\u56e0\u4e3a \uff1a1 \u2196 \u2197 -3
\u2197 \u2198
1 - 5
\u6240\u4ee5\u539f\u65b9\u7a0b\u53ef\u53d8\u5f62\uff08x-3\uff09\uff08x-5\uff09=0 \u6240\u4ee5x1=3 x2=5 \u4f8b4\u3001\u89e3\u65b9\u7a0b 6x²-5x-25=0 \u5206\u6790\uff1a\u628a6x²-5x-25\u770b\u6210\u4e00\u4e2a\u5173\u4e8ex\u7684\u4e8c\u6b21\u4e09\u9879\u5f0f,\u52196\u53ef\u4ee5\u5206\u4e3a1\u00d76,2\u00d73,-25\u53ef\u4ee5\u5206\u6210-1\u00d725,-5\u00d75,-25\u00d71.\u56e0\u4e3a \uff1a 2 \u2196 \u2197 -5
\u2197 \u2198
3 5
\u6240\u4ee5 \u539f\u65b9\u7a0b\u53ef\u53d8\u5f62\u6210\uff082x-5\uff09\uff083x+5\uff09=0 \u6240\u4ee5 x1=5/2 x2=-5/3 2)\u3001\u7528\u5341\u5b57\u76f8\u4e58\u6cd5\u89e3\u4e00\u4e9b\u6bd4\u8f83\u96be\u7684\u9898\u76ee \u4f8b5\u628a14x²-67xy+18y²\u5206\u89e3\u56e0\u5f0f \u5206\u6790\uff1a\u628a14x²-67xy+18y²\u770b\u6210\u662f\u4e00\u4e2a\u5173\u4e8ex\u7684\u4e8c\u6b21\u4e09\u9879\u5f0f,\u521914\u53ef\u5206\u4e3a1\u00d714,2\u00d77,18y²\u53ef\u5206\u4e3ay.18y ,2y.9y ,3y.6y \u56e0\u4e3a \uff1a2x \u2196 \u2197 -9y
\u2197 \u2198
7x -2y
\u6240\u4ee5 14x²-67xy+18y²= (2x-9y)(7x-2y) \u4f8b6 \u628a10x²-27xy-28y²-x+25y-3\u5206\u89e3\u56e0\u5f0f \u5206\u6790\uff1a\u5728\u672c\u9898\u4e2d,\u8981\u628a\u8fd9\u4e2a\u591a\u9879\u5f0f\u6574\u7406\u6210\u4e8c\u6b21\u4e09\u9879\u5f0f\u7684\u5f62\u5f0f \u89e3\u6cd5\u4e00\u300110x²-27xy-28y²-x+25y-3 =10x²-\uff0827y+1\uff09x -\uff0828y²-25y+3\uff09 4y -3 7y \u2573 -1 =10x²-\uff0827y+1\uff09x -\uff084y-3\uff09\uff087y -1\uff09 =[2x -\uff087y -1\uff09][5x +\uff084y -3\uff09] 2 -\uff087y \u2013 1\uff09 5 \u2573 4y - 3 =\uff082x -7y +1\uff09\uff085x +4y -3\uff09 \u8bf4\u660e\uff1a\u5728\u672c\u9898\u4e2d\u5148\u628a28y²-25y+3\u7528\u5341\u5b57\u76f8\u4e58\u6cd5\u5206\u89e3\u4e3a\uff084y-3\uff09\uff087y -1\uff09,\u518d\u7528\u5341\u5b57\u76f8\u4e58\u6cd5\u628a10x²-\uff0827y+1\uff09x -\uff084y-3\uff09\uff087y -1\uff09\u5206\u89e3\u4e3a[2x -\uff087y -1\uff09][5x +\uff084y -3\uff09]
=y^2(y^2-3y-28)
=y^2(y-7)(y+4)
\u5148\u628ay^2(\u5373y\u5e73\u65b9 \uff09\u63d0\u51fa\u6765\uff0c\u56e0\u4e3a\u6b21\u6570\u592a\u9ad8\u3002\u7136\u540e\u7528\u5341\u5b57\u4ea4\u53c9\u6cd5\u5206\u89e3\uff0c\u4e00\u822c\u5e38\u6570\u4e3a\u4e24\u6570\u4e4b\u79ef\uff0c\u4e00\u6b21\u9879\u7cfb\u6570\u4e3a\u4e24\u6570\u4e4b\u548c\u3002\u6bd4\u5982\uff1a4\u00d7\uff08-7\uff09=-28,4+\uff08-7)=-3
= y”[ y” - 3y - 28 ]
= y”[ y” + 4y - 7y - 28 ]
= y”[ y( y + 4 ) - 7( y + 4 ) ]
= y”( y + 4 )( y - 7 )
或者
= y”[ y” - 3y - 28 ]
= y”[ y” - 7y + 4y - 28 ]
= y”[ y( y - 7 ) + 4( y - 7 ) ]
= y”( y + 4 )( y - 7 )
y∧4-3y∧3-28y∧2
原式=y^2（y-7）(y+4)
=y²（y²-3y-28）
=y²（y-7）（y+4）
绛旓細1.a^4-4a+3 2.(a+x)^m+1*(b+x)^n-1-(a+x)^m*(b+x)^n 3.x^2+(a+1/a)xy+y^2 4.9a^2-4b^2+4bc-c^2 5.(c-a)^2-4(b-c)(a-b)绛旀1.鍘熷紡=a^4-a-3a+3=(a-1)(a^3+a^2+a-3)2.[1-(a+x)^m][(b+x)^n-1]3.(ax+y)(1/ax+y)4.9a^2-...
绛旓細(涓)x^2-2xy-35y^2=(x-7y)(x+5y)(浜)2x^2-7x-15=(x2+3)(x-5)(涓)20x^2-43xy+14y^2=(4x-7y)(5x-2y)(鍥)18x^2-19x+5=((2x-1)(9x-5)(浜)6x^2-13x+6=(3x-2)(2x-3)(鍏)5x^2+4xy-28y^2=(5x-14y)(x-2y)(涓)-35m^2n^2+11mn+6=-(35m²n&#...
绛旓細绗浜棰橈細 锛坅^2+b^2)^2-4a^2b^2 =a^4+2a^2b^2+b^4-4a^2b^2 =(a^2-b^2)^2 绗涓棰橈細 2(a-1)^2-12(a-1)+18 =2[(a-1)^2-6(a-1)+9 ]=2(a-1+3)^2 =2(a+2)^2 绗鍥棰橈細 -28y^4-21y^3+7y^2 =-7y^2(4y^2+3y-1)=-7y^2(4y-1)(y+1)绗簲棰...
绛旓細锛堜竴锛20x^2+锛-43xy锛+14y^2=(4x-7y)(5x-2y)锛浜锛墄^2-3xy-锛28y²锛=(x-7y)(x+4y)锛涓锛墄^2+锛3xy锛-28y^2=(x+7y)(x-4y)锛鍥锛墄^2+锛-4xy锛-21y^2=(x-7y)(x+3y)
绛旓細(2y-4)²=y²4y²-16y+16=y²3y²-16y+16=0 y=4鎴杫=4/3
绛旓細=x²(x+2)-10(x+2)=(x+2)(x²-10)-3y^4+10y²+8 =-(3y^4-10y²-8)=-(y²-4)(3y²+2)=-(y+2)(y-2)(3y²+2)3x²y+28y²+7xy²+12xy =(3x²y+12xy)+(7xy²+28y²)=3xy(x+4)+7y&#...
绛旓細4(y+3)²=(y-2)²4(y²+6y+9)=y²-4y+4 4y²+24y+36-y²+4y-4=0 3y²+28y+32=0 3(y²+28/3*y)=-32 y²+28/3*y=-32/3 y²+28/3*y+196/9=-32/3+196/9 (y+14/3)²=100/9 鎵浠+14/3=10/3锛...
绛旓細锛1锛4x-3y=14 锛2锛5x+3y=31 浠ヤ笂浜屽紡鐩稿姞 9x=45 x=5浠ｅ叆鍒帮紙2锛3y=31-25=6 y=2 锛1锛2x-5y=-21涓よ竟脳2锛屽緱锛3锛夛紙2锛4x+3y=23锛堜笌锛3锛夌浉鍑忥級锛3锛4x-10y=-42 13y=65 y=5 浠ｅ叆鍒帮紙1锛2x=-21+25=4 x=2 锛1锛4x+7y=-19锛堜笌锛2锛夌浉鍑 锛2锛4x-5y=17 12y=...
绛旓細鍏堥氬垎锛屼袱杈瑰悓涔12鍐嶇Щ椤癸紝灏嗘湭鐭ユ暟y绉诲埌涓渚э紝鍗冲彲姹傚緱y=3/2銆傝缁嗚繃绋嬪鍥
绛旓細1.M=4x²-12x+9y²+30y+35 =4x²-12x+9+9y²+30y+25+1 =(2x-3)²+(3y+5)²+1 >0 閫堿 2.15x²-47xy+28y²=0 (3x-7y)(5x-4y)=0 3x=7y 鎴 5x=4y x/y=7/3 鎴 4/5 3.2x³-x²+m = (2x+1)(ax²...
