125-[1400-(42-2.3)3]:80
1400*80=?
tính nhanh :
\(\frac{125^{100}.2^{160}}{5^{289}.4^{80}}\)
\(\frac{11.3^{22}.3^7.9^{15}}{\left(2.3^{14}\right)^2}\)
GIÚP MK VỚI CHIỀU PHẢI NỘP RÙI
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1.tính nhanh a,(4+4)×(2019+2019+...+2019) "Có 125 số 2019"
b,(42+42+...+42)+(125+125+...+125)
"Có 125 số 42 ;có 58 số 125"
a) (4+4)x(2019 +2019 +.....+2019)
= 8 x 125 x 2019
= (8 x 125) x 2019
= 1000 x 2019
= 2019000
b) ( 42+42+...+42)+(125+125+....+125)
= 42 x 125 + 58 x 125
= 125 x ( 42 + 58)
= 125 x 100
= 12500
42+42+...+42)+(125+125+....+125)
= 42 x 125 + 58 x 125
= 125 x ( 42 + 58)
= 125 x 100
= 12500
1. Tính hợp lí nếu có thể :
a) 125 + 80 + 375 + 220
b) 25.11.8.4.125
c) 18.74 + 18.27 - 18
d) 75 . 23 + 75 . 77 - 500
e) 150 : [25.(18-42)]
f) 125 . 23 . 2 . 8 . 50
g) 235 + 88 + 165 + 12
h) 71 . 32 + 71 . 68 - 1100
i) 67 : 66 + 43 .2 - 240
j) 546 - 6. [158 : (30 + 72)]
k) 268 + 147 + 132 + 253
2. Tìm số tự nhiên x, biết :
a) 7 . x = 707
b) 6x + 5 = 47
c) 35 : (x+1) = 7
d) 12 + (29 - 3x) = 35
e) 2.4x + 101 = 138
f) 7 . x = 140
g) 7 . (15 - x) + 14 = 84
h) 3x . 5 - 15 = 390
3. Tìm số tự nhiên n , biết :
(n+11) chia hết cho (n+1)
1.
a) \(125+80+375+220\)
\(=\left(125+375\right)+\left(80+220\right)\)
\(=500+300\)
\(=800\)
b) \(25.11.8.4.125\)
\(=\left(25.4\right).\left(8.125\right).11\)
\(=100.1000.11\)
\(=1100000\)
c) \(18.74+18.27-18\)
\(=18.\left(74+27-1\right)\)
\(=18.100\)
\(=1800\)
d) \(75.23+75.77-500\)
\(=75.\left(23+77\right)-500\)
\(=75.100-500\)
\(=7500-500\)
\(=7000\)
e) \(150:\left[25.\left(18-4^2\right)\right]\)
\(=150:\left[25.\left(18-16\right)\right]\)
\(=150:\left[25.2\right]\)
\(=150:50\)
\(=3\)
f) \(125.23.2.8.50\)
\(=\left(125.8\right).\left(2.50\right).23\)
\(=1000.100.23\)
\(=2300000\)
g) \(235+88+165+12\)
\(=\left(235+165\right)+\left(88+12\right)\)
\(=400+100\)
\(=500\)
h) \(71.32+71.68-1100\)
\(=71.\left(32+68\right)-1100\)
\(=71.100-1100\)
\(=7100-1100\)
\(=6000\)
i) \(6^7:6^6+4^3.2-24^0\)
\(=6+64.2-1\)
\(=6+128-1\)
\(=133\)
j) \(546-6.\left[158:\left(30+7^2\right)\right]\)
\(=546-6.\left[158:\left(30+49\right)\right]\)
\(=546-6.\left[158:79\right]\)
\(=546-6.2\)
\(=546-12\)
\(=534\)
k) \(268+147+132+253\)
\(=\left(268+132\right)+\left(147+253\right)\)
\(=400+400\)
\(=800\)
2.
a) \(7x=707\)
\(x=707:7\)
\(x=101\)
b) \(6x+5=47\)
\(6x=47-5\)
\(6x=42\)
\(x=42:6\)
\(x=7\)
c) \(35:\left(x+1\right)=7\)
\(x+1=35:7\)
\(x+1=5\)
\(x=5-1\)
\(x=4\)
d) \(12+\left(29-3x\right)=35\)
\(29-3x=35-12\)
\(29-3x=23\)
\(3x=29-23\)
\(3x=6\)
\(x=6:3\)
\(x=2\)
e) \(2.4^x+10^1=138\)
\(2.4^x=138-10\)
\(2.4^x=128\)
\(4^x=128:2\)
\(4^x=64=4^3\)
\(\Rightarrow x=3\)
f) \(7x=140\)
\(x=140:7\)
\(x=20\)
g) \(7\left(15-x\right)+14=84\)
\(7\left(15-x\right)=84-14\)
\(7\left(15-x\right)=70\)
\(15-x=70:7\)
\(15-x=10\)
\(x=15-10\)
\(x=5\)
h) \(3^x.5-15=390\)
\(3^x.5=390+15\)
\(3^x.5=405\)
\(3^x=405:5\)
\(3^x=81=3^4\)
\(\Rightarrow x=4\)
3.
Ta có:
\(\Rightarrow n+11⋮n+1\)
\(\Rightarrow n+1+10⋮n+1\)
\(\Rightarrow10⋮n+1\) hay \(n+1\inƯ\left(10\right)=\left\{-10;-5;-2;-1;1;2;5;10\right\}\)
\(\Rightarrow\) \(n\in\left\{-11;-6;-3;-2;0;1;4;9\right\}\)
Vì \(n\in N\) nên \(n\in\left\{0;1;4;9\right\}\)
Tính giá trị của các biểu thức sau:
a) \(25. 2^3 - 3^2 + 125 b) 2.3^2 + 5.(2 + 3).\)
a) 25.23 − 32 + 125 = 25.8 – 9 + 125 = 316.
b) 2.32 + 5.(2 + 3) = 2.9+5.5 = 43.
1)26.(-125)-125.(-36)
2)125.(-24)+24.225
3)42+(-19)+58-(-19)
1: \(=-26\cdot125+125\cdot36=125\cdot10=1250\)
b: \(=24\left(-125+225\right)=24\cdot100=2400\)
c: \(=42+58+19-19=100\)
(2x+1)^3=125
(2x-1)^4=16
6.3^x-2.3^x=36
2^x+1-2^x=32
\(\left(2x+1\right)^3=125\\ \Rightarrow\left(2x+1\right)^3=5^3\\ \Rightarrow2x+1=5\\ \Rightarrow2x=4\\ \Rightarrow x=2.\\ b,\left(2x-1\right)^4=16\\ \Rightarrow\left(2x-1\right)^4=2^4\\ \Rightarrow2x-1=2\\ \Rightarrow2x=3\\ \Rightarrow x=\dfrac{3}{2}.\\ c,6.3^x-2.3^x=36\\ \Rightarrow3^x.\left(6-2\right)=36\\ \Rightarrow3^x.4=36\\ \Rightarrow3^x=9\\ \Rightarrow3^x=3^2\\ \Rightarrow x=2.\\ d,2^{x+1}-2^x=32\\ \Rightarrow2^x.\left(2-1\right)=32\\ \Rightarrow2^x=2^5\\ \Rightarrow x=5.\)
96-3(x+1)=42
12x-33=3^2.3^3
giúp mình nhé!
a) 96 - 3 (x - 1) = 42
3 (x - 1) = 96 - 42
3 (x -1) = 54
x - 1 = 54 : 3
x - 1 = 18
x = 18 + 1
x = 19
b) 12x - 33 = 32 . 33
12x - 33 = 35
12x - 33 = 243
12x = 243 + 33
12x = 276
x = 276 : 12
x = 23
Bạn nhớ kiểm tra lại nha dinh nguyen
96 - 3( x+ 1 ) = 42
3( x + 1 ) = 96 - 42
3( x + 1 ) = 54
x + 1 = 54 : 3
x + 1 = 18
x = 18 - 1
x = 17
12x - 33 = 3 ^ 2 . 3 ^ 3
12x - 33 = 9 . 27
12x - 33 = 243
12x = 243 + 33
12x = 276
x = 276 : 12
x = 23
a)5^x+1=125
b)5^2x-3-2.5^2=5^2.3
c)4^x.3=16