1+2+3+....+999=?
x^2.x^4.x^6.x^8....x^48...x^50=?
tìm X
5^x=125
3^2x=81
Bài 1. Tìm x,y ϵ Z biết:
a) xy - 2x - y = 1
b) y ( x - 1 ) - x = 8
c) xy - 3x + 2y = 11
d) 2/50 + 2/48 + 2/154 + ... + 2/x(x+3) = 202/1540
e) ( 1/ 1 . 2 . 3 . 4 + 1/ 2 . 3 . 4 . 5 + 1/ 3 . 4 . 5 . 6 + ... + 1/ 7 . 8 . 9 . 10 ) . x = 119/720
Trình bày đầy đủ nhé =)))))
1: =>5(2x+6)=40
=>2x+6=8
=>2x=2
=>x=1
2: =>12-(x+3)=256:64=4
=>(x+3)=8
=>x=5
3: =>2x-1=3 hoặc 2x-1=-3
=>x=2 hoặc x=-1
4: \(\Leftrightarrow3^{x+2017}=3^{2015}\)
=>x+2017=2015
=>x=-2
1: =>5(2x+6)=40
=>2x+6=8
=>2x=2
=>x=1
2: =>12-(x+3)=256:64=4
=>(x+3)=8
=>x=5
3: =>2x-1=3 hoặc 2x-1=-3
=>x=2 hoặc x=-1
4:
=>x+2017=2015
=>x=-2
GPT:
1)(x+1006/1000)+(x+1007/999)+(x+1008/998)+(x+1009/997)+(x+2022/4)=0
2)(x-999/99)+(x-896/101)+(x-769/103)=6
3)x4+x3+6x2=-5(x+1)
4)(x+1)(x+2)(X+3)(x+4)=24
5)(x+1)(x+2)(x+4)(x+5)=40
6)(x+1/x2+x+1)-(x-1/x2-x+1)=2(x+2)2/x6-1
7)2x4-7x3-2x2+13x+6/(x+1)(2x+1)=0
8)2x4-7x3-2x2+13x+6=0
Câu 2 sai đề nhé
Phải là:(x-999)/99+(x-896)/101+(x-789/103)=6
Bài 4: Tìm các số nguyên x biết
1) |x + 2| = 4
2) 3 – |2x + 1| = (-5)
3) 12 + |3 – x| = 9
4) |x + 9| = 12 + (-9) + 2
5) 2(4x – 8) – 7(3 + x) = |-4|(3 – 2)
6) 8(x – |-7|) – 6(x – 2) = |-8|.6 – 50
7) -7(5 – x) – 2(x – 10) = 15
8) 4(x – 1) – 3(x – 2) = -|-5|
1) |x + 2| = 4
\(\Leftrightarrow\orbr{\begin{cases}x+2=4\\x+2=-4\end{cases}\Leftrightarrow}\orbr{\begin{cases}x=2\\x=-6\end{cases}}\)
2) 3 – |2x + 1| = (-5)
\(\Leftrightarrow\left|2x+1\right|=8\Leftrightarrow\orbr{\begin{cases}2x+1=8\\2x+1=-8\end{cases}\Leftrightarrow}\orbr{\begin{cases}x=\frac{7}{2}\\x=\frac{-9}{2}\end{cases}}\)
3) 12 + |3 – x| = 9
\(\Leftrightarrow\left|3-x\right|=-3\)(vô lí)
=>\(x=\varnothing\)
1) I x+2 I=4
\(\Rightarrow\orbr{\begin{cases}x+2=4\\x+2=-4\end{cases}\Leftrightarrow\orbr{\begin{cases}x=2\\x=-6\end{cases}}}\)
2) \(3-|2x+1|=-5\)
\(\Leftrightarrow|2x+1|=8\)
\(\Leftrightarrow\orbr{\begin{cases}2x+1=8\\2x+1=-8\end{cases}\Leftrightarrow\orbr{\begin{cases}2x=7\\2x=-9\end{cases}\Leftrightarrow}\orbr{\begin{cases}x=\frac{7}{2}\\x=\frac{-9}{2}\end{cases}}}\)
3) \(12+|3-x|=9\)
\(\Leftrightarrow|3-x|=-3\)(vô lí vì I 3-x I \(\ge\)0)
1; |\(x\) + 2| = 4
\(\left[{}\begin{matrix}x+2=-4\\x+2=4\end{matrix}\right.\)
\(\left[{}\begin{matrix}x=-4-2\\x=4-2\end{matrix}\right.\)
\(\left[{}\begin{matrix}x=-6\\x=2\end{matrix}\right.\)
Vậy \(x\) \(\in\) {- 6; 2}
1, x^2-3=22
2, 2x^3+5=-11
3, (x+2)^2=81
4, (2x+1)^2=25
5, 5^x+2=625
6 , (2x-3)^2=36
7,(2x-1)^3=-8
8, (x-1)^x+2=(x-1)^x+6 voi x thuoc z
9, x^2+x=0
Bài làm
a) x² - 3 = 22
=> x² = 25
=> x = + 5
Vậy x = + 5
b) 2x³ + 5 = -11
2x³ = -16
x³ = -8
x = -2
Vậy x = -2
c) ( x + 2 )² = 81
=> x + 2 = 9
=> x = 7
Vậy x = 7
d) ( 2x + 1 )² = 25
=> 2x + 1 = 5
=> 2x = 4
=> x = 2
Vậy x = 2
e) 5x + 2 = 625
5x = 623 ( vô lí )
g) ( 2x - 3 )² = 36.
=> 2x - 3 = 6
=> 2x = 9
=> x = 4,5
Vậy x = 4,5
h) ( 2x - 1 )³ = -8
=> 2x - 1 = -2
=> 2x = -1
=> x = -1/2
Vậy x = -1/2
i) ( x - 1 )x + 2 = ( x - 1 )x + 6
=> [ (x - 1 )x - ( x - 1 )x ] = 6 - 2
=> 0 = 4 ( vô lí )
Vậy x thuộc rỗng.
k) x² + x = 0
=> x( x + 1 ) = 0
=> x = 0 hoặc x + 1 = 0
=> x = 0 hoặc x = -1
Vậy x = 0 hoặc x = -1
Tìm x
a) (x+3)/200 + (x+4)/199 + (x+5)/198= -3
b) (x+4)/2000+ (x+6)/999+(x+8)/499+7=0
c) |x-4| - |2x-1|=6
Tìm x
a) (x+3)/200 + (x+4)/199 + (x+5)/198= -3
b) (x+4)/2000+ (x+6)/999+(x+8)/499+7=0
c) |x-4| - |2x-1|=6
Bài toán 3 : Tìm x, biết.
a. 2(x – 5) – 3(x + 7) = 14 b. 5(x – 6) – 2(x + 3) = 12
c. 3(x – 4) – (8 – x) = 12 d. -7(3x – 5) + 2(7x – 14) = 28
e. 5(3 – 2x) + 5(x – 4) = 6 – 4x f. -5(2 – x) + 4(x – 3) = 10x – 15
g. 2(4x – 8) – 7(3 + x) = |-4|(3 – 2) h. 8(x – |-7|) – 6(x – 2) = |-8|.6 – 50
k. -7(5 – x) – 2(x – 10) = 15 l. 4(x – 1) – 3(x – 2) = -|-5|
m. -4(x + 1) + 89x – 3) = 24 n. 5(x – 30 – 2(x + 6) = 9
o. -3(x – 5) + 6(x + 2) = 9 p. 7(x – 9) – 5(6 – x) = – 6 + 11x
q. 10(x – 7) – 8(x + 5) = 6.(-5) + 24
nhiều quá :((
\(a,2\left(x-5\right)-3\left(x+7\right)=14\)
\(2x-10-3x-21=14\)
\(-x-31=14\)
\(-x=45\)
\(x=45\)
\(b,5\left(x-6\right)-2\left(x+3\right)=12\)
\(5x-30-2x-6=12\)
\(3x-36==12\)
\(3x=48\)
\(x=16\)
\(c,3\left(x-4\right)-\left(8-x\right)=12\)
\(3x-12-8+x=0\)
\(4x-20=0\)
\(4x=20\)
\(x=5\)
Cố nốt nha bn !
cảm ơn, bn nha:)))
mà hình như bạn TOP 3 trả lời câu hỏi pải ko nhỉ???
d, \(-7\left(3x-5\right)+2\left(7x-14\right)=28\)
\(\Leftrightarrow-21x+35+14x-28=28\Leftrightarrow-7x=21\Leftrightarrow x=-3\)
e, \(5\left(3-2x\right)+5\left(x-4\right)=6-4x\)
\(\Leftrightarrow15-6x+5x-20=6-4x\Leftrightarrow-5-x=6-4x\)
\(\Leftrightarrow-11+3x=0\Leftrightarrow x=\frac{11}{3}\)
f, \(-5\left(2-x\right)+4\left(x-3\right)=10x-15\)
\(\Leftrightarrow-10+5x+4x-12=10x-15\Leftrightarrow-22+9x=10x-15\)
\(\Leftrightarrow-7-x=0\Leftrightarrow x=-7\)
Tìm x dạng có lũy thừa
1) x^2 - 3 = 22
2) 2x^3 + 5 = 11
3) ( x + 2 ) = 81
4) ( 2x + 1 ) ^2 = 25
5) 5^x + 2 = 625
6) ( 2x - 3 ) ^2 = 36
7) ( 2x - 1 ) ^3 = - 8
( x - 1 ) ^ x +2 = ( x - 1 ) ^ x + 6 với x thuộc Z 19 ^x2 + x = 0
GIÚP MÌNH NHA MÌNH ĐANG CẦN GẤP CẢM ƠN TRUÓC LUÔN NHÁ!
Tìm x,biết:
1) (x2-6x)2 - 2(x-3)2=81
2) (x+3)4 + (x+5)4=16
3) (x+2)4 + (x+8)4=272
4) (2x2-3x+1)(2x2+5x+1)=9x2
5) (x+5)(x+6)(x+10)(x+12)=6006x2