\(\Leftrightarrow\dfrac{1}{x}-\dfrac{1}{x+1}+\dfrac{1}{x+1}-\dfrac{1}{x+2}+...+\dfrac{1}{x+9}-\dfrac{1}{x+10}=\dfrac{5}{12}\)
=>\(\dfrac{x+10-x}{x\left(x+10\right)}=\dfrac{5}{12}\)
=>5x(x+10)=12*10=120
=>5x^2+50x-120=0
=>x=2 hoặc x=-12
giải phương trình:
a/x-1/x^2-x+1 - x+/x^2+x+1 = 10/x(x^4+x^2+1)
b/ x+9/10 + x+10/9 = 9/x+10 + 10/x+9
c/ x^2-2x+2/x-1 + x^2-8x+20 = x^2-4x+6/x-2 + x^2-6x +12/x-3
phân tích đa thức thành nhân tử
1)2x^2+3x-5
2)16-5x^-3
3)x^2+x-6
4)x^2+8x-9
5)x^2+x-12
6)x^8+1024
7)x^7+x^2+1
8)x^8+3x^4+4
9)(x^2+x+1)(x^2+x+2)-12
10)x(x+1)(x+2)(x+3)+1
11)x^4+6x^3+11x^2+6x+1
12)3x^2+11x^3-7x^2-2x+1
Tìm x biết
a) (x+2).(x+3) - (x-2).(x+5)=10
b) (3x+2). (2x+9) - (x+2). (8x+11)=(x+1).(3-2x)
c) 3.(2x-1).(3x-1)-(2x-3).(9x-1)=0
d) (5x-8).(4x-5)-(3x-4).(2x+12)=12
a) (x-1)(x+5)/3-(x+2)(x+5)/12=(x-1)(x+2)/4
b, 2(x-4)/3+4(x+30-x+1/8=3(2x-3)-7/5
c, x-10-7x/6+1=x/2+3(x-1)+2-x/9
d, 0,6(x+10)+0,4(11x-5)=0,7x+25,5
e, 5x-1/3+7x-1,1/3-1,5-5x/7=9x-0,7/4
g, x-4/5+3x-2/10=2x-5/3-x+2/6
1.giải các phương trình sau:
a, 3(2x+1)/4 - 5x+3/6 = 2x-1/3 - 3-x/4
b, 19/4 - 2(3x-5)/5 = 3-2x/10 - 3x-1/4
c, x-2*3/2+3 + x-3*5/3+5 + x-5*2/5+2 = 10
d, x-3/5*7 + x-5/3*7 + x-7/3*5 = 2(1/3 + 1/5 + 1/7)
2. giải các phương trình:
a, x-1/9 + x-2/8 = x-3/7 + x-4/6
b, (1/1*2 + 1/2*3 + 1/3*4 + ... + 1/9*10) (x-1) + 1/10x = x- 9/10
Giải các phương trình sau: (TM ĐK)
1) \(\dfrac{11}{x}=\dfrac{9}{x+1}+\dfrac{2}{x-4}\)
2) \(\dfrac{14}{3x-12}-\dfrac{2+x}{x-4}=\dfrac{3}{8-2x}-\dfrac{5}{6}\)
3) \(\dfrac{x+5}{x^2-5x}-\dfrac{x+25}{2x^2-50}=\dfrac{x-5}{2x^2+10}\)
4) \(\dfrac{x+1}{x-1}-\dfrac{x-1}{x+1}=\dfrac{16}{x^2-1}\)
5) \(\left(1-\dfrac{x-1}{x+1}\right)\left(x+2\right)=\dfrac{x+1}{x-1}+\dfrac{x-1}{x+1}\)
mng giúp mk bài này nha. Cảm ơn bạn nhiều
- Bài 12: Thực hiện phép tính
1) x(1 - x) + (x - 1) ^ 2 3) (x + 2) ^ 2 - (x - 3)(x + 1)
5) (x - 2) ^ 2 + (x - 1)(x + 5)
7) (1 - 2x)(5 - 3x) + (4 - x) ^ 2
9) (x + 1) ^ 2 + (x - 2)(x + 2) - 4x
11) (x + 4) ^ 2 + (x + 5)(x - 5) - 2x(x + 1)
13) (x - 1) ^ 2 - 2(x + 3)(x - 3) + 4x(x - 4)
2) (x - 3) ^ 2 - x ^ 2 + 10x - 7
4) (x + 4)(x - 2) - (x - 3) ^ 2
6) (x + 3)(x - 3) - x(23 + x)
8) (x - 2)(x + 2) - (x - 3)(x + 1)
10) (x + 2) ^ 2 - (x + 3)(x - 3) + 10
12) (x - 1) ^ 2 - (x - 4)(x + 4) + (x + 3) ^ 2
14) (y - 3)(y + 3)(y ^ 2 + 9) -(y^ 2 +2)(y
Phân tích đa thức thành nhân tử:
1.45+x^3-5*x^2-9*x
2.x^4-2*x^3-2*x^2-2*x+3
3.x^4-5*x^2+4
4.x^4+64
5.x^5+x^4+1
6.(x^2+2*x)*(x^2+2*x+4)+3
7.(x^3+4*x+8)^2+3*x*(x^2+4*x+8)+2*x^2
8. x^3*(x^2-7)^2-36*x
9.x^5+x+1
10. x^8+x^4+1
11. x^5-x^4-x^3-x^2-x-2
12. x^9-x^7-x^6-x^5+x^4+x^3+x^2-1
13. (x^2-x)^2-12*(x^2-x)+24
Giải pt:
a) | 5x | = 3x + 8
b) | -4x | = -2x + 11
c) | 3x - 1 | = 4x + 1
d) | 3 - 2x | = 3x - 7
e) 9 - | -5x | + 2x = 0
f) ( x + 1)² + | x + 10 | - x² - 12 = 0
g) | 4 - x | + x² - (5 + x)x = 0
h) | x - 1 | = | 2x - 3|
i) | x| + | x + 2 | = 4
k) | 2x + 1 | - | 5x - 2 | = 3
l) 2 | x | - | x + 3 | - 1 = 0
