1樓:時間在流逝
原式=x^5-(x^2-1)+2=x^2(x^3-1)+3=x^2(x-1)(x^2+x+1)+3
=(x+1)(x-1)*2x+3
=(x^2-1)*2x+3
=2x^2+3
=2x+5
=6±√5
2樓:總代
有理數混合運算
(一)計算題:
(1)23+(-73)
(2)(-84)+(-49)
(3)7+(-2.04)
(4)4.23+(-7.57)
(5)(-7/3)+(-7/6)
(6)9/4+(-3/2)
(7)3.75+(2.25)+5/4
(8)-3.75+(+5/4)+(-1.5)
(二)用簡便方法計算:
(1)(-17/4)+(-10/3)+(+13/3)+(11/3)
(2)(-1.8)+(+0.2)+(-1.7)+(0.1)+(+1.8)+(+1.4)
(1)(+1.3)-(+17/7)
(2)(-2)-(+2/3)
(3)|(-7.2)-(-6.3)+(1.1)|
(4)|(-5/4)-(-3/4)|-|1-5/4-|-3/4|)
(1)(-4)(+6)(-7)
(2)(-27)(-25)(-3)(-4)
(3)0.001*(-0.1)*(1.1)
(4)24*(-5/4)*(-12/15)*(-0.12)
(5)(-3/2)(-4/3)(-5/4)(-6/5)(-7/6)(-8/7)
(6)(-24/7)(11/8+7/3-3.75)*24
(二)用簡便方法計算:
(1)(-71/8)*(-23)-23*(-73/8)
(2)(-7/15)*(-18)*(-45/14)
(3)(-2.2)*(+1.5)*(-7/11)*(-2/7)
[-|98|+76+(-87)]*23[56+(-75)-(7)]-(8+4+3)
5+21*8/2-6-59
68/21-8-11*8+61
-2/9-7/9-56
4.6-(-3/4+1.6-4-3/4)
1/2+3+5/6-7/12
[2/3-4-1/4*(-0.4)]/1/3+2
22+(-4)+(-2)+4*3
-2*8-8*1/2+8/1/8
(2/3+1/2)/(-1/12)*(-12)
(-28)/(-6+4)+(-1)
2/(-2)+0/7-(-8)*(-2)
(1/4-5/6+1/3+2/3)/1/2
18-6/(-3)*(-2)
(5+3/8*8/30/(-2)-3
(-84)/2*(-3)/(-6)
1/2*(-4/15)/2/3
(1)-1+2-3+4-5+6-7;
(2)-50-28+(-24)-(-22);
(3)-19.8-(-20.3)-(+20.2)-10.8;
(4)0.25- +(-1 )-(+3 ).
11、8-4÷(-2); 12、-9+5×(-6)-12÷(-6)
14、-1-〔1-(1-0.6÷3)〕×〔2-(-3)×(-4)〕;
20、0÷(-4)-42-(-8)÷(-1)3;
21、-32-(-3) 2-(-3)3+(-1)6;
24、3×(-2)2+(-2×3)2+(-2+3)2;
34、(-12)÷4×(-6)÷2;
36、(-12)÷4×(-6)÷2;
[-|98|+76+(-87)]*23[56+(-75)-(7)]-(8+4+3)
5+21*8/2-6-59
68/21-8-11*8+61
-2/9-7/9-56
4.6-(-3/4+1.6-4-3/4)
1/2+3+5/6-7/12
[2/3-4-1/4*(-0.4)]/1/3+2
22+(-4)+(-2)+4*3
-2*8-8*1/2+8/1/8
(2/3+1/2)/(-1/12)*(-12)
(-28)/(-6+4)+(-1)
2/(-2)+0/7-(-8)*(-2)
(1/4-5/6+1/3+2/3)/1/2
18-6/(-3)*(-2)
(5+3/8*8/30/(-2)-3
(-84)/2*(-3)/(-6)
1/2*(-4/15)/2/3
(-71/8)*(-23)-23*(-73/8)
(2)(-7/15)*(-18)*(-45/14)
(3)(-2.2)*(+1.5)*(-7/11)*(-2/7)
解一元一次方程 練習題
1 . 2x-10.3x=15
2 . 0.52x-(1-0.52)x=80
3 . x/2+3x/2=7
4 . 3x+7=32-2x
5 . 3x+5(138-x)=540
6 . 3x-7(x-1)=3-2(x+3)
7 . 18x+3x-3=18-2(2x-1)
8 . 3(20-y)=6y-4(y-11)
9 . -(x/4-1)=5
10. 3[4(5y-1)-8]=6
(1)2x+5=5x-7 (2) 4-3(2-x)=5x
(3)3(x-2)=2-5(x-2) (4) 2(x+3)-5(1-x)=3(x-1)
(1)6x=3x-12 (2)2y―1 = y―3
(3)-2x=-3x+8 (4)56=3x+32-2x
(5)3x―7+6x=4x―8 (6)7.9x+1.58+x=7.9x-8.42
1)-2(x-1)=4 (2)3(x-2)+1=x-(2x-1) (3)3x-[3(x+1)-(1+4)]=l
整式加減
3.3ab-4ab+8ab-7ab+ab=______ 4.7x-(5x-5y)-y=______.
5.23a3bc2-15ab2c+8abc-24a3bc2-8abc=______.
6.-7x2+6x+13x2-4x-5x2=______. 7.2y+(-2y+5)-(3y+2)=______.
11.(2x2-3xy+4y2)+(x2+2xy-3y2)=______. 12.2a-(3a-2b+2)+(3a-4b-1)=______. 13.-6x2-7x2+15x2-2x2=______.
14.2x-(x+3y)-(-x-y)-(x-y)=______. 16.2x+2y-[3x-2(x-y)]=______. 17.5-(1-x)-1-(x-1)=______.
18.( )+(4xy+7x2-y2)=10x2-xy.
19.(4xy2-2x2y)-( )=x3-2x2y+4xy2+y3.
44.-2(3x+z)-(-6x)+(-5y+3z)=______.
45.-5an-an+1-(-7an+1)+(-3an)=______.
46.3a-(2a-4b-6c)+3(-2c+2b)=______.
48.9a2+[7a2-2a-(-a2+3a)]=______.
(-y+6+3y4-y3)-(2y2-3y3+y4-7)
-(2x2-y2)-[2y2-(x2+2xy)]
3a-(2a-3b)+3(a-2b)-b
3x-[y-(2x+y)
-3x2y+5xy2-6xy2+4-7x2y-9
3m2n+6mn2-mn2-m2n
(3x-5y)-(6x+7y)+(9x-2y)
(2)2a-[3b-5a-(3a-5b)]
(3)(6m2n-5mn2)-6(m2n-mn2)
(1)m2+(-mn)-n2+(-m2)-(-0.5n2)
(2)2(4an+2-an)-3an+(an+1-2an+1)-(8an+2+3an)
(3)化簡:(x-y)2-(x-y)2-[(x-y)2-(x-y)2]
1)a-(a-3b+4c)+3(-c+2b)
(2)(3x2-2xy+7)-(-4x2+5xy+6)
(3)2x2-
(二)化簡
(1)a>0,b<0,|6-5b|-|3a-2b|-|6b-1|
(2)1
1、(7m二次方-4mn+n的二次方)-4(2m的二次方-mn+2n的二次方) 2、15a的二次方- 3.5adc- 70.(4x2-8x+5)-(x3+3x2-6x+2). 72.(0.3x3-x2y+xy2-y3)-(-0.5x3-x2y+0.3xy2). 73.-{2a2b-[3abc-(4ab2-a2b)]}. 74.(5a2b+3a2b2-ab2)-(-2ab2+3a2b2+a2b). 75.(x2-2y2-z2)-(-y2+3x2-z2)+(5x2-y2+2z2). 76.(3a6-a4+2a5-4a3-1)-(2-a+a3-a5-a4). 77.(4a-2b-c)-5a-[8b-2c-(a+b)]. 78.(2m-3n)-(3m-2n)+(5n+m). 79.(3a2-4ab-5b2)-(2b2-5a2+2ab)-(-6ab). 80.xy-(2xy-3z)+(3xy-4z). 81.(-3x3+2x2-5x+1)-(5-6x-x2+x3). 83.3x-(2x-4y-6x)+3(-2z+2y). 84.(-x2+4+3x4-x3)-(x2+2x-x4-5). 85.若a=5a2-2ab+3b2,b=-2b2+3ab-a2,計算a+b. 86.已知a=3a2-5a-12,b=2a2+3a-4,求2(a-b). 87.2m-{-3n+[-4m-(3m-n)]}. 88.5m2n+(-2m2n)+2mn2-(+m2n). 89.4(x-y+z)-2(x+y-z)-3(-x-y-z). 90.2(x2-2xy+y2-3)+(-x2+y2)-(x2+2xy+y2). 92.2(a2-ab-b2)-3(4a-2b)+2(7a2-4ab+b2). 94.4x-2(x-3)-3[x-3(4-2x)+8]. (四)將下列各式先化簡,再求值 97.已知a+b=2,a-b=-1,求3(a+b)2(a-b)2-5(a+b)2×(a-b)2的值. 98.已知a=a2+2b2-3c2,b=-b2-2c2+3a2,c=c2+2a2-3b2,求(a-b)+c. 99.求(3x2y-2xy2)-(xy2-2x2y),其中x=-1,y=2. 126.去括號,合併同類項: (1)(m+1)-(-n+m); (2)4m-[5m-(2m-1)]. 127.化簡:2x2-{-3x-[4x2-(3x2-x)+(x-x2)]}. 128.化簡:-(7x-y-2z)-{[4x-(x-y-z)-3x+z]-x}. 129.計算:(+3a)+(-5a)+(-7a)+(-31a)-(+4a)-(-8a). 130.化簡:a3-(a2-a)+(a2-a+1)-(1-a4+a3). 131.將x2-8x+2x3-13x2-2x-2x3+3先合併同類項,再求值,其中x=-4. 好像用了那啥叫做配原法吧。先要從後面那個代數式下手 用配原法 把 3變成 1 4 目的是為了能用十字相乘 前面的x三次方 2x的二次方 1 就變成了 x 1 x x 1 然後加上那個4 式子就變成了 x 1 x x 1 4 由一式得x x 1 0 將 x 1 x x 1 4 中的 x x 1 變成0... 會有天使愛鬼王 你好 樓上答案都不對!解 a 2 ab b 2 a 2 2ab b 2 3ab a b 2 3ab 4 2 3 12 16 36 20 a b 2 a b 2 4ab 4 2 4 12 16 48 32 在實數範圍內,你的題目有問題 因為a b 4,代入第二式得,b 2 4b 12 ... 解 當a 0,b 0時 a a b b ab ab 1 1 1 3 當a 0,b 0時 a a b b ab ab 1 1 1 1 當a 0,b 0時 a a b b ab ab 1 1 1 1 當a 0,b 0時 a a b b ab ab 1 1 1 1綜上 a a b b ab ab 3或 1...已知x x 1 0,求代數式x 2x平方 3的值過程詳細,主要是x是怎麼變過來的好的直接滿分
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