tính
( 5 mũ 9 x 7 mũ 5- 5 mũ 10 x 7 mũ 5 :5 ) : 2017 mũ 2018
C = 5 + 5 mũ 2 - 5 mũ 3 + 5 mũ 4 - 5 mũ 25 + ....... - 5 mũ 2017 +5 mũ 2018
( x -5 ) mũ 2013 = ( x - 6 ) mũ 2016
( x + 1 ) mũ 3 = 27
(2x+1 ) mũ 3 = 9*81
2 mũ x + 16 mũ 2 = 1024
\(\left(x+1\right)^3=27\)
\(\left(x+1\right)^3=3^3\)
\(\Rightarrow x+1=3\)
\(x=2\)
\(\left(x+1\right)^3=27\)
\(< =>\left(x+1\right)^3=3.3.3=3^3\)
\(< =>x+1=3< =>x=3-1=2\)
\(\left(2x+3\right)^3=9.81\)
\(< =>\left(2x+3\right)^3=9.9.9\)
\(< =>\left(2x+3\right)^3=9^3\)
\(< =>2x+3=9< =>2x=6\)
\(< =>x=\frac{6}{2}=3\)
giúp mình bài này đi
21.73 + 27 . 21
1. 6 X mũ 3 -8 =40
2. 4 X mũ 5 +15=47
3. 2 X mũ 3-4=12
4. 5 X mũ 3-5=0
5. (X -5) mũ 2016 = (X-5) mũ 2018
6. (3X -2) mũ 20= (3X-1) mũ 20
7. (3X -1) mũ 10 = (3X-1) mũ 20
8. (2X -1) mũ 50 = 2X-1
9. (X phần 3 -5) mũ 2000= ( X phần 3-5) mũ 2008
1. \(6x^3-8=40\\ 6x^3=48\\ x^3=8\\ \Rightarrow x=2\)Vậy x = 2
2. \(4x^5+15=47\\ 4x^5=32\\ x^5=8\\ \Rightarrow x\in\varnothing\left(\text{vì }x\in N\right)\)Vậy x ∈ ∅
3. \(2x^3-4=12\\ 2x^3=16\\ x^3=8\\ \Rightarrow x=2\)Vậy x = 2
4. \(5x^3-5=0\\ 5x^3=5\\ x^3=1\\ \Rightarrow x=1\)Vậy x = 1
5. \(\left(x-5\right)^{2016}=\left(x-5\right)^{2018}\\ \Rightarrow\left[{}\begin{matrix}x-5=0\\x-5=1\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=5\\x=6\end{matrix}\right.\)Vậy \(x\in\left\{5;6\right\}\)
6. \(\left(3x-2\right)^{20}=\left(3x-1\right)^{20}\\ \Rightarrow3x-2=3x-1\\ 3x-3x=2-1\\ 0=1\left(\text{vô lí}\right)\)Vậy x ∈ ∅
7. \(\left(3x-1\right)^{10}=\left(3x-1\right)^{20}\\ \left(3x-1\right)^{10}=\left[\left(3x-1\right)^2\right]^{10}\\ \Rightarrow\left(3x-1\right)^2=3x-1\\ \left(3x-1\right)^2-\left(3x-1\right)=0\\ \left(3x-1\right)\left[\left(3x-1\right)-1\right]=0\\ \left(3x-1\right)\left(3x-2\right)=0\\ \Rightarrow\left[{}\begin{matrix}3x-1=0\\3x-2=0\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}3x=1\\3x=2\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=\frac{1}{3}\left(\text{loại vì }x\in N\right)\\x=\frac{2}{3}\left(\text{loại vì }x\in N\right)\end{matrix}\right.\)Vậy x ∈ ∅
8. \(\left(2x-1\right)^{50}=2x-1\\ \left(2x-1\right)^{50}-\left(2x-1\right)=0\\ \left(2x-1\right)\left[\left(2x-1\right)^{49}-1\right]=0\\ \Rightarrow\left[{}\begin{matrix}2x-1=0\\\left(2x-1\right)^{49}=1\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}2x=1\\2x-1=1\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}x=\frac{1}{2}\left(\text{loại vì }x\in N\right)\\x=1\left(t/m\right)\end{matrix}\right.\)Vậy x = 1
9. \(\left(\frac{x}{3}-5\right)^{2000}=\left(\frac{x}{3}-5\right)^{2008}\\ \left(\frac{x}{3}-5\right)^{2008}-\left(\frac{x}{3}-5\right)^{2000}=0\\ \left(\frac{x}{3}-5\right)^{2000}\left[\left(\frac{x}{3}-5\right)^8-1\right]=0\\ \Rightarrow\left[{}\begin{matrix}\left(\frac{x}{3}-5\right)^{2000}=0\\\left(\frac{x}{3}-5\right)^8=1\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}\frac{x}{3}-5=0\\\frac{x}{3}-5=1\\\frac{x}{3}-5=-1\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}\frac{x}{3}=5\\\frac{x}{3}=6\\\frac{x}{3}=4\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}x=5\cdot3=15\\x=6\cdot3=18\\x=4\cdot3=12\end{matrix}\right.\)Vậy \(x\in\left\{15;18;12\right\}\)
\(1.6x^3-8=40\\ \Leftrightarrow6x^3=48\\ \Leftrightarrow x^3=8\Leftrightarrow x^3=2^3=\left(-2\right)^3\Leftrightarrow\left[{}\begin{matrix}x=2\\x=-2\end{matrix}\right.\)
Vậy \(x\in\left\{2;-2\right\}\)
\(2.4x^3+15=47\) (T nghĩ đề là mũ 3)
\(\Leftrightarrow4x^3=32\Leftrightarrow x^3=8=2^3=\left(-2\right)^3\Leftrightarrow\left[{}\begin{matrix}x=2\\x=-2\end{matrix}\right.\)
Vậy \(x\in\left\{2;-2\right\}\)
Câu 3, 4 tương tự nhé.
\(5.\left(x-5\right)^{2016}=\left(x-5\right)^{2018}\\ \Leftrightarrow\left(x-5\right)^{2018}-\left(x-5\right)^{2016}=0\\ \Leftrightarrow\left(x-5\right)^{2016}\left[\left(x-5\right)^2-1\right]=0\\ \Leftrightarrow\left(x-5\right)^{2016}\left(x-5-1\right)\left(x-5+1\right)=0\\ \Leftrightarrow\left(x-5\right)^{2016}\left(x-6\right)\left(x-4\right)=0\\ \Leftrightarrow\left[{}\begin{matrix}\left(x-5\right)^{2016}=0\\x-6=0\\x-4=0\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x-5=0\\x=6\\x=4\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x=5\\x=6\\x=4\end{matrix}\right.\)
Vậy \(x\in\left\{4;5;6\right\}\)
xin cho hỏi bài tính nhanh 6 mà kiểu 87 + 24 = 24-13) 87+13 để ra số tròn chục á nah tôi cần đáp của vài bài sau:
a)3 mũ 2 x 5 + 2 mũ 3 x 10 - 81 : 3
b)20 : 2 mũ 2 +5 mũ 9: 5 mũ 8
c)100 : 5 mũ 2 +7 x 3 mũ 2
d) 5 mũ 13 ; 5 mũ 10 -25 x 2 mũ 2
e) 84 : 4 + 3 mũ 9 : 3 mũ 7 + 5 mũ 0
f)( 5 mũ 19 : 5 mũ 17 +3) : 7
g)1200 : 2 + 6 mũ 2 x 2 mũ 1 + 18
h)5 mũ 9 : 5 mũ 7 + 70 : 14 - 20.
Bài 2: Tìm số tự nhiên x,biết:
1, 2 mũ x = 4
2, 2 mũ x = 8
3, 2 mũ x = 16
4, 2 mũ x = 1
5, 3 mũ x = 9
6, 3 mũ x = 81
7, 3 mũ x = 27
8, 5 mũ x = 25
9, 5 mũ x = 125
10, 8 mũ x = 64
11, 3 mũ x + 1 = 3 mũ 2
12, 2 mũ 2 x + 1 = 2 mũ 7
13, 5 mũ x - 1 = 5 mũ 2
14, 5 mũ 2 x - 4 = 5 mũ 10
15, 6 x + 4 = 6 mũ 10
16, 2 mũ 2 x - 3 = 2 mũ 9
17, 7 mũ 2 x - 3 = 7 mũ 7
18, 8 mũ x - 2 = 1
19, 9 mũ x - 8 = 81
20, 10 mũ 2 x - 1 = 1000
Giúp mình với,mình đang cần gấp !!
Bài 1:
2\(x\) = 4
2\(^x\) = 22
\(x=2\)
Vậy \(x=2\)
Bài 2:
2\(^x\) = 8
2\(^x\) = 23
\(x=3\)
Vậy \(x=3\)
Bài 3
2\(^x\) = 16
2\(^x\) = 24
\(x=4\)
Vậy \(x=4\)
Rút gọn : a, 3 mũ 10 . -5 mũ 21 / -5 mũ 20. 3 mũ 12
b, -11 mũ 5 . 13 mũ 7 / 11 mũ 5 . 13 mũ 8
c, 2 mũ 10 . 3 mũ 10 - 2 mũ 10 . 3 mũ 9 / 2 mũ 9 . 3 mũ 10
d, 5 mũ 11 .7 mũ 12 + 5 mũ 11 . 7 mũ 11 / 5 mũ 12 . 7 mũ 12 + 9 . 5 mũ 11 . 7 mũ 11
a)\(\frac{3^{10}.\left(-5\right)^{21}}{\left(-5\right)^{20}.3^{12}}=\frac{-5}{9}\)
b)\(\frac{\left(-11\right)^5.13^7}{11^5.13^8}=-\frac{1}{13}\)
c)\(\frac{2^{10}.3^{10}-2^{10}.3^9}{2^9.3^{10}}=\frac{2^{10}.3^9\left(3-1\right)}{2^9.3^{10}}=2\)
d(\(\frac{5^{11}.7^{12}+5^{11}.7^{11}}{5^{12}.7^{12}+9.5^{11}.7^{11}}=\frac{5^{11}.7^{11}\left(7+1\right)}{5^{11}.7^{11}\left(35+9\right)}=\frac{1}{6}\)
mấy bạn tính nhanh cho mình câu này với
5 mũ 5 : 5 mũ 3 - 5
1. b. 5 mũ 3 .2 -100 : 4 + 2 mũ 3 .5
c. 6 mũ 2 :9 + 50.2 -3 mũ 3. 3
d. 3 mũ 2 .5 + 2 mũ 3 .10 - 81:3
e. 5 mũ 13 : 5 mũ 10 - 25. 2 mũ 2
f. 20 : 2 mũ 2 + 5 mũ 9 : 5 mũ 8
g. 100 : 5 mũ 2 + 7 . 3 mũ 2
h.84 : 4 + 3 mũ 9 : 3 mũ 7 + 5 mũ 0
i. 29- [16+3 .(51-49)
J. ( 15 mũ 19: 5 mũ 17 + 3) 0 : 7
k. 7 mũ 9 : 7 mũ 7 - 3 mũ 2 + 2 mũ 3 . 5 mũ 2
l. 1200:2+6 mũ 2 . 2 mũ 1 + 18
m. 5 mũ 9 : 5 mũ 7 + 70 :14 -20
n. 3 mũ 2 . 5 - 2 mũ 2 .7 + 83
o. mũ 9 : 5 mũ 7+ 12.3 + 7 mũ 0
p. 5 . 2 mũ 2 + 98 : 7 mũ 2
q. 3 mũ 11 : 3 mũ 9 _ 147 : 7 mũ 2
r. 295 - ( 31 - 2 mũ 2 . 5 ) mũ 2
s. 151 - 2 mũ 91 : 2 mũ 88 + 1 mũ 2 . 3
t. 2 mũ 38 : 2 mũ 36 + 5 mũ 1 . 3 mũ 2 - 7 mũ 2
u. 7 mũ 91 : 7 mũ 89 + 5. 5 mũ 2 - 124
v. 4 . 15 + 28:7-6 mũ 20 : 6 mũ 18
w. ( 3 mũ 2 + 2 mũ 3 . 5 ) : 7
x. 11 mũ 25 : 11 mũ 23 - 3 mũ 5 : ( 1 mũ 10 + 2 mũ 3 ) - 60
y. 5 mũ 20 : ( 5 mũ 15 . 6 + 5 mũ 15 . 19)
z. 7 mũ 18 : 7 mũ 16 + 2 mũ 2 . 3 mũ 3
t.59. 73- 30 mũ 2 + 27 . 59
a,\(5^3.2-100:4+2^3.5\)
= 125 . 2 - 25 + 8 . 5
= 250 - 25 + 40
= 265
b, \(6^2:9+50.2-3^3.3\)
= 36 : 9 + 100 - 27 . 3
= 4 + 100 - 81
= 23
b) \(5^3\cdot2-100:4+2^3\cdot5\)
\(=125\cdot2-25+8\cdot5\)
\(=250-25+40\)
\(=225+40=265\)
c) \(6^2:9+50\cdot2+3^3-3\)
\(=36:9+100+27-3\)
\(=4+100+27-3\)
\(=104+27-3=131-3=128\)
d) \(3^2\cdot5+2^3\cdot10-81:3\)
\(=9\cdot5+8\cdot10-27\)
\(=45+80-27\)
\(=125-27=98\)
e) \(5^{13}:5^{10}-25\cdot2^2\)
\(=5^{13-10}-5^2\cdot2^2\)
\(=5^3-\left(5\cdot2\right)^2\)
\(=125-10^2\)
\(=125-100=25\)
f) \(20:2^2+5^9:5^8\)
\(=20:4+5^{9-8}\)
\(=5+5^1=5+5=10\)
g) \(100:5^2+7\cdot3^2\)
\(=10^2:5^2+7\cdot9\)
\(=\left(10:5\right)^2+63\)
\(=2^2+63=4+63=67\)
h) \(84:4+3^9:3^7+5^0\)
\(=21+3^{9-7}+1\)
\(=21+3^2+1\)
\(=21+9+1=30+1=31\)
i) \(29-\left[16+3\cdot\left(51-49\right)\right]\)
\(=29-\left[16+3\cdot2\right]\)
\(=29-\left[16+6\right]\)
\(=29-22=7\)
j) \(\left(15^{19}:5^{17}+3\right)\cdot0:7\)
\(=\left[\left(3\cdot5\right)^{19}:5^{17}+3\right]\cdot0\)
Vì số nào nhân cho 0 cũng bằng 0 nên giá trị biểu thức trên bằng 0
k) \(7^9:7^7-3^2+2^3\cdot5\)
\(=7^{9-7}-9+8\cdot5\)
\(=7^2-9+40\)
\(=49-9+40=40+40=80\)
l) \(1200:2+6^2\cdot2^1+18\)
\(=600+36\cdot2+18\)
\(=600+72+18\)
\(=600+\left(72+18\right)=600+90=690\)
m) \(5^9:5^7+70:14-20\)
\(=5^{9-7}+5-20\)
\(=5^2+5-20\)
\(25+5-20=30-20=10\)
Những câu sau mình làm sau nhé bạn!!!!!!!
\(\dfrac{5\cdot4^{15}\cdot9^9-4\cdot3^{20}\cdot8^9}{5\cdot2^{29}\cdot9^{10}-7\cdot2^{29}\cdot27^6}\)
\(=\dfrac{5\cdot2^{30}\cdot3^{18}-2^2\cdot2^{27}\cdot3^{20}}{5\cdot2^{29}\cdot3^{20}-7\cdot2^{29}\cdot3^{18}}\)
\(=\dfrac{2^{29}\cdot3^{18}\left(5\cdot2-3^2\right)}{2^{29}\cdot3^{18}\left(5\cdot3^2-7\right)}\)
\(=\dfrac{10-9}{5\cdot9-7}=\dfrac{1}{38}\)
tính giá trị các biểu thức sau:
a) 2 mũ 3 .3 mũ 2
b)5 mũ 10 :5 mũ 7
c 2 mũ 6 : 2
d 7 mũ 4 : 7 mũ 4
e 9 mũ 5 : 9 mũ 5
giúp mình vs ạ ..
a) \(2^3.3^2=8.9=72\)
b) \(5^{10}:5^7=5^2=25\)
c) \(2^6:2=2^5=32\)
d) \(7^4:7^4=7^0=1\)
e) \(9^5:9^5=9^0=1\)