(x-2)^2-6=43
a) x + 29 = |-43| + (-43)
b) |x| - (-2) = (-1)
c)(-1) + 3 + (-5) + 7 +....+x = 600
g) 2 + (-4) + 6 + (-8) +.....+ ( -x) = -2000
a, \(x+29=\left|-43\right|+\left(-43\right)\)
\(\Rightarrow x+29=0\)
\(\Rightarrow x=-29\)
c, \(\left(-1\right)+3+\left(-5\right)+7+...+x=600\)
\(\Rightarrow2+2+....+x=600\)
Để kết quả bằng 600 thì phải có 3000 cặp số tương ứng có 600 số trong dãy số và x là số 600 cuối cùng \(\Rightarrow x=1199\)
g, \(2+\left(-4\right)+6+\left(-8\right)+...+\left(-x\right)=-2000\)
\(\Leftrightarrow\left(-2\right)+\left(-2\right)+...+\left(2\right)=-2000\)
\(\Leftrightarrow\left(-2\right).\left(\dfrac{x-2}{2}+1\right)=-200\)
\(\Leftrightarrow\dfrac{x-2}{2}+1=400\)
\(\Leftrightarrow x=800\)
-Chúc bạn học tốt-
Giải:
a) \(x+29=\left|-43\right|+\left(-43\right)\)
\(x+29=43+\left(-43\right)\)
\(x+29=0\)
\(x=0-29\)
\(x=-29\)
b) \(\left|x\right|-\left(-2\right)=\left(-1\right)\)
\(\left|x\right|=\left(-1\right)+\left(-2\right)\)
\(\left|x\right|=-3\)
Vì giá trị tuyệt đối của một số ko bao giờ đc kết quả là số âm nên x ∈ ∅.
c) \(\left(-1\right)+3+\left(-5\right)+7+...+x=600\)
\(\Rightarrow2+2+...+2=600\)
\(\Rightarrow2.\left(\dfrac{x-1}{2}+1\right):2=600\)
\(\Rightarrow\dfrac{x-1}{2}+1=600\)
\(\Rightarrow\dfrac{x-1}{2}=599\)
\(\Rightarrow x-1=1198\)
\(\Rightarrow x=1199\)
Chúc bạn học tốt!
b; |\(x\)| - (-2) = (-1)
|\(x\)| + 2 = -1
|\(x\)| = - 1 - 2
|\(x\)| = -3 (vô lý vì |\(x\)| ≥ 0 ∀\(x\)
Vậy \(x\in\varnothing\)
1. x - 8 +32= 68
2. x +8+32=68
3. 98-x +34=43
4. 98+x-34=43
5. x :5:4=800
6. 18+x=384:8
7. (84,6-2 x x):3,02= 5,1
8. x x5= 120:6
9. (15x 24-x) :0,25= 100:0,25
1. \(x-8+32=68\)
\(x-8=68-32\)
\(x-8=36\)
\(x=36+8\)
\(x=44\)
_____
2. \(x+8+32=68\)
\(x+8=68-32\)
\(x+8=36\)
\(x=36-8\)
\(x=28\)
_____
3. \(98-x+34=43\)
\(98-x=43-34\)
\(98-x=9\)
\(x=98-9\)
\(x=89\)
_____
4. \(98+x-34=43\)
\(98+x=43+34\)
\(98+x=77\)
\(x=77-98\)
\(x=-21\)
_____
5. \(x:5:4=800\)
\(x:5=800.4\)
\(x:5=3200\)
\(x=3200.5\)
\(x=16000\)
_____
6. \(18+x=384:8\)
\(18+x=48\)
\(x=48-18\)
\(x=30\)
_____
7. \(\left(84,6-2\times x\right):3,02=5,1\)
\(84,6-2.x=5,1.3,02\)
\(84,6-2.x=15,402\)
\(2.x=84,6-15,402\)
\(2.x=69,198\)
\(x=69,198:2\)
\(x=34,599\)
_____
8. \(x\times5=120:6\)
\(x.5=20\)
\(x=20:5\)
\(x=4\)
_____
9. \(\left(15\times24-x\right):0,25=100:0,25\)
\(\left(15.24-x\right):0,25=400\)
\(15.24-x=400.0,25\)
\(15.24-x=100\)
\(360-x=100\)
\(x=360-100\)
\(x=260\)
1,x-8+32=68
=>x-8=68-32=36
=>x=36+8=42
2,x+8+32=68
=>x+8=68-32=36
=>x=36-8=28
3,98-x+34=43
=>98-x=43-34=9
=>x=98-9=89
4,98+x-34=43
=>98+x=43+34=77
=>x=77-98=-21
5,x:5:4=800
=>x:20=800
=>x=800x20=16000
6,18+x=384:8=48
=>x=48-18=30
7,(84,6-2x):3,02=5,1
=>84,6-2x=5,1x3,02=15,402
=>2x=84,6-15,402=69,198
=>x=69,198:2=34,599
8,5x=120:6=20
=>x=20:5=4
9,(15x24-x):0,25=100:0,25=400
=>360-x=400x0,25=100
=>x=360-100=260.
1. \(...\Rightarrow x+24=68\Rightarrow x=68-24=44\)
2. \(...\Rightarrow x+40=68\Rightarrow x=68-40=28\)
3. \(...\Rightarrow3^{2\left(8+x\right)}=9=3^2\Rightarrow2\left(8+x\right)=2\Rightarrow8+x=1\Rightarrow x=-7\)
4. \(...\Rightarrow3^{2\left(8+x\right)}=77\) (bạn xem lại đề)
5. \(...\Rightarrow x:5=800.4\Rightarrow x:5=3200\Rightarrow x=3200.5=16000\)
6. \(...\Rightarrow18+x=48\Rightarrow x=48-18=30\)
7. \(...\Rightarrow84,6-2x=5,1.3,02=15,402\Rightarrow2x=84,6-15,402\Rightarrow2x=69,198\Rightarrow x=34,599\)
8. \(...\Rightarrow5.x=20\Rightarrow x=20:5=4\)
9. \(\left(360-x\right):0,25=400\Rightarrow360-x=400.0,25=100\Rightarrow x=400-100=300\)
(102+2*62)/(43*x)=2
\(\frac{\text{( 100 + 72)}}{43x}=\frac{172}{43x}\Rightarrow172:2=86\)
=>\(86:43=2\)
vậy x=2
Tìm x
(102 + 2 . 62) : (43 . x) = 2
(102 + 2 . 62) : (43.x) =2
(100 + 2 . 36 ) : (43x) = 2
(100 + 72 ) : (43x) = 2
=> 172 : (43x) =2
=> 43x=172:2
=> 43x=86
=> x=86:43
=> x=2
3(x-1)2=26+43
3(x-1)2=2 49
x-1 =2 49+6
x-1 =8 49
x =8 49-1
x =9 49
3737 x 43 - 4343 x 37 / 2 + 4 + 6 + ... +100
3737 x 43 - 4343 x 37 / 2 + 4 + 6 + ... +100
= 3737 x 43 - 4343 x 37 / 2 + 4 + 6+ ....+ 100
= 0/ 2 + 4+ 6 + ...+ 100
= 0
het rui
2 . (-2)3 + 5 . (-6) - (-26)
-12 + (17-x) = 6
(x-1)2 = 4
57 . (43-14) - 43 . (57+14)
Do bài này dễ nên ai làm đúng và nhanh nhất thì mink sẽ k cho :*
1/ \(2.\left(-2\right)^3+5.\left(-6\right)-\left(-26\right)\)
\(=2.8+\left(-30\right)-\left(-26\right)\)
\(=16+\left(-30\right)-\left(-26\right)\)
\(=-14-\left(-26\right)\)
\(=12\)
2/ \(\left(-12\right)+\left(17-x\right)=6\)
\(17-x=6-\left(-12\right)\)
\(17-x=18\)
\(x=17-18=-1\)
3/ \(\left(x-1\right)^2=4\)
\(\Rightarrow\left(x-1\right)^2=2^2\)
\(\Rightarrow x-1=2\)
\(\Rightarrow x=3\)
Chúc bạn học tốt nha
2.(-2)^3+5.(-6)-(-26)=2.(-8)+5.(-6)-(-26)=(-16)+(-30)-(-26)=-20
-12+(17-x)=6
17-x=6-(-12)
17-x=18
x=17-18
x=-1
(x-1)^2=4
=>x-1=2
x=2+1
x=3
57.(43-14)-43.(57+14)=57.29-43.71=1653-3053=-1400
Tìm số tự nhiên x, biết :
a. 10 + 2.x = 45 : 43 b. 2.x - 138 = 23.32 c. 231 - ( x - 6 ) = 1339 : 13
a: =>2x+10=4^2=16
=>2x=6
=>x=3
b: =>2x-138=8*9=72
=>2x=138+72=210
=>x=105
c: =>231-(x-6)=103
=>x-6=128
=>x=134
\(a.10+2x=4^5:4^3\\ \Leftrightarrow10+2x=4^2\\ \Leftrightarrow2x=6\\ \Leftrightarrow x=3\)
\(b.2x-138=2^3.3^2\\ \Leftrightarrow2x-138=72\\ \Leftrightarrow x=210:2\\ \Leftrightarrow x=105\)
\(c.231-\left(x-6\right)=1339:13\\ \Leftrightarrow231-\left(x-6\right)=103\\ \Leftrightarrow x-6=128\\ \Leftrightarrow x=134\)
Chú ý : Nếu bạn chưa học \(\Leftrightarrow\) thì bạn bỏ đi nha !
bài 1 : tinh gtri biểu thức
c, 78 + 22 x (96 : 3+ 20 )
d,( 779 : 41 x 16) x ( 435 - 249)
bài 2 : tính nhanh
a, 137 x 6 + 63 x 6 + 200 x 4
b. 42 x 43 + 43 x 57 + 43
c, 754 x 75 - 2262 x 25 + 4568
Bài 1: Máy tính nha bạn
Bài 2
a)\(137.6+63.6+200.4\)
\(=6\left(137+63\right)+200.4\)
\(=6.200+200.4\)
\(=200.\left(6+4\right)=200.10=2000\)
b)\(42.43+43.57+43\)
\(=43\left(42+57+1\right)\)
\(=43.100=4300\)
c)\(754.75-2262.25+4568\)
=\(754.3.25-2262.25+4568\)
\(=2262.25-2262.25+4568\)
\(=0+4568=4568\)