|6-|x+1|=1
a.A=1 1/2 x 1 1/3 x 1 1/4 x 1 1/5 x...x1 1/2020 x 1 1/2021
b.B=1 1/2 + 1 1/6 + 1 1/12 +1 1/20+ ... + 1 1/380 + 1 1/420
c.C=1 6/8 x 1 6/18 x 1 6/30 x 1 6/44 x ... x 1 6/10700
a.A=1 1/2 x 1 1/3 x 1 1/4 x 1 1/5 x...x1 1/2020 x 1 1/2021
b.B=1 1/2 + 1 1/6 + 1 1/12 +1 1/20+ ... + 1 1/380 + 1 1/420
c.C=1 6/8 x 1 6/18 x 1 6/30 x 1 6/44 x ... x 1 6/10700
a.A=1 1/2 x 1 1/3 x 1 1/4 x 1 1/5 x...x1 1/2020 x 1 1/2021
b.B=1 1/2 + 1 1/6 + 1 1/12 +1 1/20+ ... + 1 1/380 + 1 1/420
c.C=1 6/8 x 1 6/18 x 1 6/30 x 1 6/44 x ... x 1 6/10700
1. (x-6)^2 = 2(x-6)
2. 2(x-3)^2 = (x-3)(x+5)
3. 4(x-3)=2x-5(2x+3)
4. x2 +4 -2 (x-1) = (x-2)^2
5. x-3/5 = 6 - 1-2x/3
6. x+2 = 6-5x/2
7. x+2/5 - x+3 = x-2/2
8. 2x-5/x-4 = 2x+1/x+2
9. X+3/x-3 - x-1/x+3 = x2 + 4x + 6/x2 -9
10. 3x-3/x2-9 -1/x-3 = x+1/x+3
11. X+1/x-1 - x-1/x+1 = 4/x2 -1
Bài dài quá, lần sau chia nhỏ câu hỏi nhé!!!!!
tìm x
x-6 1/2=6 1/3+6 1/6
x-3/7=1/2+3/7
x-3/5=1/3:1/6
x:3/2=5/6-3/8
Mình sẽ trả lời từng câu một nhé:
x-6 1/2=6 1/3+6 1/6
x-13/2=19/3+37/6
x-13/2=38/6+37/6
x-13/2=75/6
x =75/6+13/2
x =75/6+39/6
x =19
x-3/7=1/2+3/7
x-3/7=7/14+6/14
x-3/7=13/14
x =13/14+3/7
x =13/14+6/14
x =19/14
x-3/5=1/3:1/6
x-3/5=1/3x6
x-3/5=2
x =2+3/5
x =10/5+3/5
x =13/5
x:3/2=5/6-3/8
x:3/2=40/48-18/48
x:3/2=11/24
x =11/24x3/2
x =3/16
3/5 + 2/5 : x = 1 1/10
( x - 3/5) x 3/8 - 5/8 = 1/6
1 1/6 - 5/6 : ( x+1/4) = 1/2
SOS
`3/5+2/5:x=1 1/10`
`3/5+2/5:x=11/10`
`2/5:x=11/10-3/5=1/2`
`x=2/5:1/2=4/5`
_______________________________________________________
`(x-3/5)xx3/8-5/8=1/6`
`(x-3/5)xx3/8=1/6+5/8`
`(x-3/5)xx3/8=4/24+15/24=19/24`
`x-3/5=19/24:3/8=19/9`
`x=19/9+3/5=122/45`
_______________________________________________________
`1 1/6-5/6:(x+1/4)=1/2`
`7/6-5/6:(x+1/4)=1/2`
`5/6:(x+1/4)=7/6-1/2=2/3`
`x+1/4=5/6:2/3=5/4`
`x=5/4-1/4=4/4=1`
1/x(x+3) + 1/(x+3)(x+6) +1/(x+6)(x+9) + 1/(x+9)(x+12) =1/16
\(\Leftrightarrow\dfrac{3}{x\left(x+3\right)}+\dfrac{3}{\left(x+3\right)\left(x+6\right)}+...+\dfrac{3}{\left(x+9\right)\left(x+12\right)}=\dfrac{3}{16}\)
=>\(\dfrac{1}{x}-\dfrac{1}{x+3}+\dfrac{1}{x+3}-\dfrac{1}{x+6}+...+\dfrac{1}{x+9}-\dfrac{1}{x+12}=\dfrac{3}{16}\)=>\(\dfrac{1}{x}-\dfrac{1}{x+12}=\dfrac{3}{16}\)
=>\(\dfrac{x+12-x}{x\left(x+12\right)}=\dfrac{3}{16}\)
=>12/x(x+12)=3/16
=>4/x(x+12)=1/16
=>x(x+12)=64
=>x^2+12x-64=0
=>x^2+16x-4x-64=0
=>(x+16)(x-4)=0
=>x=4 hoặc x=-16
rút gọn BT
A= (x+1/x)^6 - ( x^6 +1/x^6) -2 : ( x+1/x)^3 +x^3 +1/x^3
Tính:
a) (6 : \(\dfrac{3}{5}\) \(1\dfrac{1}{6}\) x \(\dfrac{6}{7}\) ) : ( \(4\dfrac{1}{5}\) x \(\dfrac{10}{11}\) + \(5\dfrac{2}{11}\) )
b) (\(1-\dfrac{1}{2}\)) x (\(1-\dfrac{1}{3}\)) x (\(1-\dfrac{1}{4}\)) x ..... x (\(1-\dfrac{1}{2003}\)) x (\(1-\dfrac{1}{2007}\))