关于因式分解的数学题诶... 初二数学因式分解题100道
\u5173\u4e8e\u6570\u5b66\u56e0\u5f0f\u5206\u89e3\u9898\u76ee1\u3001\uff08xy\uff09²-3xy-10
=(xy-5)(xy+2)
2. x²-y²+y-¼
=x²-(y²-y+1/4)
=x²-(y-1/2)²
=(x+y-1/2)(x-y+1/2)
3. \u5df2\u77e5x²-5x-1=0\uff0c\u6c42x-\uff08x\u5206\u4e4b\u4e00\uff09\uff0cx²+\uff08x²\u5206\u4e4b\u4e00\uff09\u7684\u503c
x²-5x-1=0\uff0c\u5f97x²-1=5x
\u540c\u9664x\u5f97\uff1ax-1/x=5
\uff08x-1/x)²=25
\u5f97x²+1/x²=23
4. \u586b\u7a7a\uff1a1x2x3x4+1=(5 )²\uff1b
2x3x4x5+1=( 11 )²
11x12x13x14+1=(155 )²
36x37x38x39+1=( 1405 )²
\u7528\u4f60\u5b66\u8fc7\u7684\u6587\u5b57\u8bed\u8a00\u6982\u62ec\u4ee5\u4e0a\u7b97\u5f0f\u7684\u89c4\u5f8b\uff08\u56db\u4e2a\u8fde\u7eed\u81ea\u7136\u6570\u7684\u4e58\u79ef\u52a01\u7b49\u4e8e\u4e2d\u95f4\u4e8c\u6570\u4e58\u79ef\u51cf1\u7684\u5e73\u65b9 \uff09
\u5e76\u7528\u5b66\u8fc7\u7684\u56e0\u5f0f\u5206\u89e3\u7684\u77e5\u8bc6\u6765\u8bf4\u660e\u8fd9\u4e2a\u89c4\u5f8b\u3002
x(x+1)(x+2)(x+3)+1
=x(x+3)(x+1)(x+2)+1
=(x²+3x+2-2)(x²+3x+2)+1
=(x²+3x+2)²-2(x²+3x+2)+1
=(x²+3x+2)²
=((x+1)(x+2))²
1.\u628a\u4e0b\u5217\u5404\u5f0f\u5206\u89e3\u56e0\u5f0f
\uff081\uff0912a3b2\uff0d9a2b+3ab;
\uff082\uff09a\uff08x+y\uff09\uff0d\uff08a\uff0db\uff09\uff08x+y\uff09;
\uff083\uff09121x2\uff0d144y2;
\uff084\uff094\uff08a\uff0db\uff092\uff0d\uff08x\uff0dy\uff092;
\uff085\uff09\uff08x\uff0d2\uff092+10\uff08x\uff0d2\uff09+25;
\uff086\uff09a3\uff08x+y\uff092\uff0d4a3c2.
2.\u7528\u7b80\u4fbf\u65b9\u6cd5\u8ba1\u7b97
\uff081\uff096.42\uff0d3.62;
\uff082\uff0921042\uff0d1042
\uff083\uff091.42\u00d79\uff0d2.32\u00d736
\u7b2c\u4e8c\u7ae0 \u5206\u89e3\u56e0\u5f0f\u7efc\u5408\u7ec3\u4e60
\u4e00\u3001\u9009\u62e9\u9898
1.\u4e0b\u5217\u5404\u5f0f\u4e2d\u4ece\u5de6\u5230\u53f3\u7684\u53d8\u5f62\uff0c\u662f\u56e0\u5f0f\u5206\u89e3\u7684\u662f\uff08 \uff09
(A)(a+3)(a-3)=a2-9 (B)x2+x-5=(x-2)(x+3)+1
(C)a2b+ab2=ab(a+b) (D)x2+1=x(x+ )
2.\u4e0b\u5217\u5404\u5f0f\u7684\u56e0\u5f0f\u5206\u89e3\u4e2d\u6b63\u786e\u7684\u662f\uff08 \uff09
(A)-a2+ab-ac= -a(a+b-c) (B)9xyz-6x2y2=3xyz(3-2xy)
(C)3a2x-6bx+3x=3x(a2-2b) (D) xy2+ x2y= xy(x+y)
3.\u628a\u591a\u9879\u5f0fm2(a-2)+m(2-a)\u5206\u89e3\u56e0\u5f0f\u7b49\u4e8e\uff08 \uff09
(A)(a-2)(m2+m) (B)(a-2)(m2-m) (C)m(a-2)(m-1) (D)m(a-2)(m+1)
4.\u4e0b\u5217\u591a\u9879\u5f0f\u80fd\u5206\u89e3\u56e0\u5f0f\u7684\u662f\uff08 \uff09
(A)x2-y (B)x2+1 (C)x2+y+y2 (D)x2-4x+4
5.\u4e0b\u5217\u591a\u9879\u5f0f\u4e2d\uff0c\u4e0d\u80fd\u7528\u5b8c\u5168\u5e73\u65b9\u516c\u5f0f\u5206\u89e3\u56e0\u5f0f\u7684\u662f\uff08 \uff09
(A) (B) (C) (D)
6.\u591a\u9879\u5f0f4x2+1\u52a0\u4e0a\u4e00\u4e2a\u5355\u9879\u5f0f\u540e\uff0c\u4f7f\u5b83\u80fd\u6210\u4e3a\u4e00\u4e2a\u6574\u5f0f\u7684\u5b8c\u5168\u5e73\u65b9\uff0c\u5219\u52a0\u4e0a\u7684\u5355\u9879\u5f0f\u4e0d\u53ef\u4ee5\u662f\uff08 \uff09
(A)4x (B)-4x (C)4x4 (D)-4x4
7.\u4e0b\u5217\u5206\u89e3\u56e0\u5f0f\u9519\u8bef\u7684\u662f\uff08 \uff09
(A)15a2+5a=5a(3a+1) (B)-x2-y2= -(x2-y2)= -(x+y)(x-y)
(C)k(x+y)+x+y=(k+1)(x+y) (D)a3-2a2+a=a(a-1)2
8.\u4e0b\u5217\u591a\u9879\u5f0f\u4e2d\u4e0d\u80fd\u7528\u5e73\u65b9\u5dee\u516c\u5f0f\u5206\u89e3\u7684\u662f\uff08 \uff09
(A)-a2+b2 (B)-x2-y2 (C)49x2y2-z2 (D)16m4-25n2p2
9.\u4e0b\u5217\u591a\u9879\u5f0f\uff1a\u246016x5-x\uff1b\u2461(x-1)2-4(x-1)+4\uff1b\u2462(x+1)4-4x(x+1)+4x2\uff1b\u2463-4x2-1+4x\uff0c\u5206\u89e3\u56e0\u5f0f\u540e\uff0c\u7ed3\u679c\u542b\u6709\u76f8\u540c\u56e0\u5f0f\u7684\u662f\uff08 \uff09
(A)\u2460\u2461 (B)\u2461\u2463 (C)\u2462\u2463 (D)\u2461\u2462
10.\u4e24\u4e2a\u8fde\u7eed\u7684\u5947\u6570\u7684\u5e73\u65b9\u5dee\u603b\u53ef\u4ee5\u88ab k\u6574\u9664\uff0c\u5219k\u7b49\u4e8e\uff08 \uff09
(A)4 (B)8 (C)4\u6216-4 (D)8\u7684\u500d\u6570
\u4e8c\u3001\u586b\u7a7a\u9898
11.\u5206\u89e3\u56e0\u5f0f\uff1am3-4m= .
12.\u5df2\u77e5x+y=6\uff0cxy=4\uff0c\u5219x2y+xy2\u7684\u503c\u4e3a .
13.\u5c06xn-yn\u5206\u89e3\u56e0\u5f0f\u7684\u7ed3\u679c\u4e3a(x2+y2)(x+y)(x-y)\uff0c\u5219n\u7684\u503c\u4e3a .
14.\u82e5ax2+24x+b=(mx-3)2\uff0c\u5219a= \uff0cb= \uff0cm= . (\u7b2c15\u9898\u56fe)
15.\u89c2\u5bdf\u56fe\u5f62\uff0c\u6839\u636e\u56fe\u5f62\u9762\u79ef\u7684\u5173\u7cfb\uff0c\u4e0d\u9700\u8981\u8fde\u5176\u4ed6\u7684\u7ebf\uff0c\u4fbf\u53ef\u4ee5\u5f97\u5230\u4e00\u4e2a\u7528\u6765\u5206\u89e3\u56e0\u5f0f\u7684\u516c\u5f0f\uff0c\u8fd9\u4e2a\u516c\u5f0f\u662f .
\u4e09\u3001(\u6bcf\u5c0f\u98986\u5206\uff0c\u517124\u5206)
16.\u5206\u89e3\u56e0\u5f0f\uff1a(1)-4x3+16x2-26x (2) a2(x-2a)2- a(2a-x)3
\uff083\uff0956x3yz+14x2y2z\uff0d21xy2z2 (4)mn(m\uff0dn)\uff0dm(n\uff0dm)
17.\u5206\u89e3\u56e0\u5f0f\uff1a(1) 4xy\u2013(x2-4y2) (2)- (2a-b)2+4(a - b)2
18.\u5206\u89e3\u56e0\u5f0f\uff1a(1)-3ma3+6ma2-12ma (2) a2(x-y)+b2(y-x)
19\u3001\u5206\u89e3\u56e0\u5f0f
\uff081\uff09 \uff1b \uff082\uff09 \uff1b
\uff083\uff09 \uff1b
20.\u5206\u89e3\u56e0\u5f0f\uff1a(1) ax2y2+2axy+2a (2)(x2-6x)2+18(x2-6x)+81 (3) \u20132x2n-4xn
21\uff0e\u5c06\u4e0b\u5217\u5404\u5f0f\u5206\u89e3\u56e0\u5f0f\uff1a
\uff081\uff09 \uff1b \uff082\uff09 \uff1b \uff083\uff09 \uff1b
22\uff0e\u5206\u89e3\u56e0\u5f0f\uff081\uff09 \uff1b \uff082\uff09 \uff1b
23.\u7528\u7b80\u4fbf\u65b9\u6cd5\u8ba1\u7b97\uff1a
(1)57.6\u00d71.6+28.8\u00d736.8-14.4\u00d780 (2)39\u00d737-13\u00d734
\uff083\uff09\uff0e13.7
24\uff0e\u8bd5\u8bf4\u660e\uff1a\u4e24\u4e2a\u8fde\u7eed\u5947\u6570\u7684\u5e73\u65b9\u5dee\u662f\u8fd9\u4e24\u4e2a\u8fde\u7eed\u5947\u6570\u548c\u76842\u500d\u3002
25\uff0e\u5982\u56fe\uff0c\u5728\u4e00\u5757\u8fb9\u957f\u4e3aa\u5398\u7c73\u7684\u6b63\u65b9\u5f62\u7eb8\u677f\u56db\u89d2\uff0c\u5404\u526a\u53bb\u4e00\u4e2a\u8fb9\u957f\u4e3a b(b< )\u5398\u7c73\u7684\u6b63\u65b9\u5f62\uff0c\u5229\u7528\u56e0\u5f0f\u5206\u89e3\u8ba1\u7b97\u5f53a=13.2\uff0cb=3.4\u65f6\uff0c\u5269\u4f59\u90e8\u5206\u7684\u9762\u79ef\u3002
26\uff0e\u5c06\u4e0b\u5217\u5404\u5f0f\u5206\u89e3\u56e0\u5f0f
\uff081\uff09
\uff082\uff09 \uff1b
(3) (4)
(5)
(6)
(7) (8)
(9) \uff0810\uff09(x2+y2)2-4x2y2
\uff0812\uff09\uff0ex6n+2+2x3n+2+x2 \uff0813\uff09\uff0e9(a+1)2(a-1)2-6(a2-1)(b2-1)+(b+1)2(b-1)2
27.\u5df2\u77e5(4x-2y-1)2+ =0\uff0c\u6c424x2y-4x2y2+xy2\u7684\u503c.
28\uff0e\u5df2\u77e5\uff1aa=10000\uff0cb=9999\uff0c\u6c42a2+b2\uff0d2ab\uff0d6a+6b+9\u7684\u503c\u3002
29\uff0e\u8bc1\u660e58-1\u89e3\u88ab20\u223d30\u4e4b\u95f4\u7684\u4e24\u4e2a\u6574\u6570\u6574\u9664
30.\u5199\u4e00\u4e2a\u591a\u9879\u5f0f\uff0c\u518d\u628a\u5b83\u5206\u89e3\u56e0\u5f0f(\u8981\u6c42\uff1a\u591a\u9879\u5f0f\u542b\u6709\u5b57\u6bcdm\u548cn\uff0c\u7cfb\u6570\u3001\u6b21\u6570\u4e0d\u9650\uff0c\u5e76\u80fd\u5148\u7528\u63d0\u53d6\u516c\u56e0\u5f0f\u6cd5\u518d\u7528\u516c\u5f0f\u6cd5\u5206\u89e3).
31.\u89c2\u5bdf\u4e0b\u5217\u5404\u5f0f\uff1a
12+(1\u00d72)2+22=9=32
22+(2\u00d73)2+32=49=72
32+(3\u00d74)2+42=169=132
\u2026\u2026
\u4f60\u53d1\u73b0\u4e86\u4ec0\u4e48\u89c4\u5f8b\uff1f\u8bf7\u7528\u542b\u6709n(n\u4e3a\u6b63\u6574\u6570)\u7684\u7b49\u5f0f\u8868\u793a\u51fa\u6765\uff0c\u5e76\u8bf4\u660e\u5176\u4e2d\u7684\u9053\u7406.
32.\u9605\u8bfb\u4e0b\u5217\u56e0\u5f0f\u5206\u89e3\u7684\u8fc7\u7a0b\uff0c\u518d\u56de\u7b54\u6240\u63d0\u51fa\u7684\u95ee\u9898\uff1a
1+x+x(x+1)+x(x+1)2=(1+x)[1+x+x(x+1)]
=(1+x)2(1+x)
=(1+x)3
(1)\u4e0a\u8ff0\u5206\u89e3\u56e0\u5f0f\u7684\u65b9\u6cd5\u662f \uff0c\u5171\u5e94\u7528\u4e86 \u6b21.
(2)\u82e5\u5206\u89e31+x+x(x+1)+x(x+1)2+\u2026+ x(x+1)2004\uff0c\u5219\u9700\u5e94\u7528\u4e0a\u8ff0\u65b9\u6cd5 \u6b21\uff0c\u7ed3\u679c\u662f .
(3)\u5206\u89e3\u56e0\u5f0f\uff1a1+x+x(x+1)+x(x+1)2+\u2026+ x(x+1)n(n\u4e3a\u6b63\u6574\u6570).
34\uff0e\u82e5a\u3001b\u3001c\u4e3a\u25b3ABC\u7684\u4e09\u8fb9\uff0c\u4e14\u6ee1\u8db3a2+b2+c2\uff0dab\uff0dbc\uff0dca=0\u3002\u63a2\u7d22\u25b3ABC\u7684\u5f62\u72b6\uff0c\u5e76\u8bf4\u660e\u7406\u7531\u3002
35\uff0e\u9605\u8bfb\u4e0b\u5217\u8ba1\u7b97\u8fc7\u7a0b\uff1a
99\u00d799+199=992+2\u00d799+1=\uff0899+1\uff092=100 2=10 4
1\uff0e\u8ba1\u7b97\uff1a
999\u00d7999+1999=____________=_______________=_____________=_____________\uff1b
9999\u00d79999+19999=__________=_______________=______________=_______________\u3002
2\uff0e\u731c\u60f39999999999\u00d79999999999+19999999999\u7b49\u4e8e\u591a\u5c11\uff1f\u5199\u51fa\u8ba1\u7b97\u8fc7\u7a0b\u3002
36.\u6709\u82e5\u5e72\u4e2a\u5927\u5c0f\u76f8\u540c\u7684\u5c0f\u7403\u4e00\u4e2a\u6328\u4e00\u4e2a\u6446\u653e\uff0c\u521a\u597d\u6446\u6210\u4e00\u4e2a\u7b49\u8fb9\u4e09\u89d2\u5f62(\u5982\u56fe1)\uff1b\u5c06\u8fd9\u4e9b\u5c0f\u7403\u6362\u4e00\u79cd\u6446\u6cd5\uff0c\u4ecd\u4e00\u4e2a\u6328\u4e00\u4e2a\u6446\u653e\uff0c\u53c8\u521a\u597d\u6446\u6210\u4e00\u4e2a\u6b63\u65b9\u5f62(\u5982\u56fe2).\u8bd5\u95ee\uff1a\u8fd9\u79cd\u5c0f\u7403\u6700\u5c11\u6709\u591a\u5c11\u4e2a\uff1f
\u56fe1 \u56fe2
x - 7x + 6 = 0 (x - 1)(x - 6) = 0 x1 = 1 x2 = 6 这是用“十字相乘”法解的。 “十字相乘”法简介 把二次项的系数分为两个数的乘积,此处1 = 1 × 1,常数项也分为两个数的乘积,此处 6 = (-1) × (-6), 而后交叉相乘,得到的两个乘积求和,这个和与一次项的系数相等即可,此处 1 × (-1) + 1 × (-6) = -7。 这个方法书上讲的很少,这是因为该方法适应范围较窄,不是通用的方法,练习时,可以优先使用该方法,如果不能解决问题,在换用配方法。 “配方”法简介 配方法简单易行,适应范围广,是必须掌握的方法。 1、如果二次项的系数不为“1”,则从二次项和一次项的系数中提取到括号的前面; 2、在括号内添加“一次项系数一半的平方”,在减去“一次项系数一半的平方”; 3、括号内的前三项可直接写出完全平方式。 对于本例,做法如下 x - 7x + 6 = 0 x - 7x + (-7/2) - (-7/2) + 6 = 0 (x - 7/2) - 49/4 + 6 = 0 (x - 7/2) - 25/4 = 0 (x - 7/2) - (5/2) = 0 (x - 7/2 + 5/2)(x - 7/2 - 5/2) = 0 (x - 1)(x - 6) = 0
绛旓細=(x^n+3)²-y²=(x^n+3+y)(x^n+3-y)x²(x²+y²)-2y^4 =x^4+x²y²-2y^4 =(x²+2y²)(x²-y²)=(x²+2y²)(x+y)(x-y)x²+3x-(a²+a-2)=涓嶈兘鍒嗚В m³+4m^4-5-20m...
绛旓細杩欓鐢ㄥ崄瀛楃浉涔樻硶锛氬師寮=(x+3y)(x-2y)鍥犲紡鍒嗚В涓鑸敤鍏紡娉(骞虫柟宸叕寮忥紝瀹屽叏骞虫柟鍏紡锛岀珛鏂瑰拰宸叕寮忕瓑)锛屽崄瀛楃浉涔樻硶锛屾彁鍙栧叕鍥犲紡娉锛屾垨鍒欑敤姹傛牴鍏紡
绛旓細鍘熷紡=(x^2+y^2)^2+(x^4+y^4)=(x^2+y^2)^2+(x^2+y^2)^2 =2(x^2+y^2)^2 =2(x+y)^4 鎵嶅鐨鍥犲紡鍒嗚В锛屼笉鐭ラ亾瀵逛笉瀵璇銆傘傞渶璋呰В锛佸笇鏈涙槸鏈浣冲洖绛擿``~~~
绛旓細...=999脳999+999脳2+1=(999+1)²=10000000 ...=(x+y+1)²...=[2(a-b)+4(a+b)][2(a-b)-4(a+b)]=(6a+2b)(-2a-6b)...=-2b(a²-2a+1)=-2b(a-1)²...=绗叚棰樻湁鐐逛笉姝e父璇銆傜湅鐪嬮鏈夋病鏈夋墦閿欏晩锛屾墦閿欎簡杩介棶涓涓嬨...=(a²+1+...
绛旓細鎶10鎷嗘垚1+9 (4a²+4a+1)+(b²-6b+9)=0 (2a+1)²+(b-3)²=0 骞虫柟澶т簬绛変簬0锛岀浉鍔犵瓑浜0 鑻ユ湁涓涓ぇ浜0锛屽垯鍙︿竴涓皬浜0锛屼笉鎴愮珛銆傛墍浠ヤ袱涓兘绛変簬0 鎵浠2a+1=0,b-3=0 a=-1/2,b=3 鍘熷紡=ab(a²+b²)=-3/2脳(1/4+9)=-111/8 ...
绛旓細x^2-100x+2000=0 ⌈x-(50-10鈭5) ⌉[x-(50+10鈭5) ]=0 x=50+10鈭5 鎴50-10鈭5 x^2-45x-650=0 [x-(45-5鈭185) ][x-(45+5鈭185) ]=0 x=45+5鈭185 鎴45-5鈭185 鍏跺疄鍙槸鏍圭殑鍏紡搴旂敤鑰屽凡锛屽姞娌癸細锛...
绛旓細鍘熷紡锛漻锛坸骞虫柟锛峹锛4鍒嗕箣1锛夛紳x锛坸锛2鍒嗕箣1锛夊钩鏂
绛旓細杩欎釜杩欓亾棰樻庝箞鍋氱殑锛熶粬鏄鍥犲紡鍒嗚В瀵瑰惂锛熶粈涔堟槸鍥犲紡鍒嗚В灏辨槸鎻愬彇鍏洜寮忓鎶婂畠鍖栦负鏈绠锛岀劧鍚庤繖閬撻鎬庝箞鍋氬憿锛熼鍏堟垜浠湅涓涓嬪畠鏄痻鐨勫钩鏂癸紝鍑忔嫭鍙穣+z鎷彿鐨勫钩鏂癸紝瀵瑰惂锛熺劧鍚庤繖涓繖涓庝箞鍋氬憿锛熻繖涓枃鎴戜滑鍙兘涓嶈繖涓垜浠偗瀹氭槸涓嶈兘鍘诲悗闈㈤偅涓嫭鍙风殑瀵瑰惂锛熻繖涓嫭鍙蜂竴鍘讳粬灏变笉鑳藉仛浜嗭紝鎵浠ヨ繖閬撻鏄...
绛旓細2 16a²-5=(4a-鈭5)(4a+鈭5)x²+2鈭2+2=(x+鈭2)²7x²-1=(鈭7x-1)(鈭7x+1)x^4-4x²+4=(x²-2)²=(x-鈭2)²(x+鈭2)²3 (a+1)(b-1)=ab-a+b-1=ab-(a-b)-1=鈭3-2鈭3+1-1= -鈭3 (杩欎釜棰樻槸涓...
绛旓細渚1銆 鍒嗚В鍥犲紡x -2x -x(2003娣畨甯備腑鑰冮) x -2x -x=x(x -2x-1) 2銆 搴旂敤鍏紡娉 鐢变簬鍒嗚В鍥犲紡涓庢暣寮忎箻娉曟湁鐫浜掗嗙殑鍏崇郴,濡傛灉鎶婁箻娉曞叕寮忓弽杩囨潵,閭d箞灏卞彲浠ョ敤鏉ユ妸鏌愪簺澶氶」寮忓垎瑙e洜寮忋 渚2銆佸垎瑙e洜寮廰 +4ab+4b (2003鍗楅氬競涓冮) 瑙:a +4ab+4b =(a+2b) 3銆 鍒嗙粍鍒嗚В娉 瑕佹妸澶氶」寮廰m+an+...