a) ( x - 3 ) mũ 2 -1 = 24
b) ( x + 2 ) mũ 3 = 64
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
a, 100 - 7 ( x - 5 ) = 31 + 33
100 - 7 ( x - 5 ) = 31 + 27
100 - 7 ( x - 5 ) = 58
7 ( x - 5 ) = 100 - 58
7 ( x - 5 ) = 42
x - 5 = 42 : 7
x - 5 = 6
=> x = 6 +5
=> x = 11
Vậy x = 11
b, 12 ( x - 1 ) : 3 = 43 + 23
12 ( x - 1 ) : 3 = 64 + 8
12 ( x - 1 ) : 3 = 72
12 ( x - 1 ) = 72 . 3
12 ( x - 1 ) = 216
x - 1 = 216 : 12
x - 1 = 18
=> x = 18 + 1
=> x = 19
Vậy x = 19
c, 24 + 5x = 75 : 73
24 + 5x = 72
24 + 5x = 49
5x = 49 - 24
5x = 25
=> x = 25 : 5
=> x = 5
Vậy x = 5
d, 5x - 206 = 24 . 4
5x - 206 = 16 . 4
5x - 206 = 64
5x = 64 + 206
5x = 270
=> x = 270 : 5
=> x = 54
Vậy x = 54
e, 125 = x3
53 = x3
=> x = 5
Vậy x = 5
g, 64 = x2
82 = x2
=> x = 8
Vậy x = 8
a) \(3^2.x+2^3.x=51\)
\(\Leftrightarrow x\left(3^2+2^3\right)=51\)
\(\Leftrightarrow17x=51\)
\(\Leftrightarrow x=3\)
Vậy
b) \(6^2.2-\left(84-3^2.x\right):7=69\)
\(\Leftrightarrow\left(84-3^2.x\right):7=3\)
\(\Leftrightarrow84-3^2.x=21\)
\(\Leftrightarrow3^2.x=63\)
\(\Leftrightarrow x=7\)
Vậy
a: \(3^x-2=2^7\)
\(\Leftrightarrow3^x=128+2=130\)(vô lý)
b: \(4^{x+1}=64\)
=>x+1=3
hay x=2
c: \(\left(5x+1\right)^2=1^{2016}=1\)
=>5x+1=1 hoặc 5x+1=-1
=>x=0 hoặc x=-2/5
d: \(2^{2\left(x-1\right)}=8\)
=>2(x-1)=3
=>x-1=3/2
hay x=5/2
a. x mũ 2 - 2x + 1 = 25
= x^2 + 2.x.1 + 1^2
= ( x + 1 ) ^2
ko bt có đúng ko nữa, mấy câu kia tui ko bt lm
a) 5x = 125
5x = 53
=> x = 3
b) x3 = 64
x3 = 43
=> x = 4
c) ( x - 1 ) 2 = 25
( x - 1 ) 2 = 52
=> x - 1 = 5
=> x = 5 + 1
=> x = 6
d) 5x + 5x+2 = 130
5x . 1 + 5x . 52 = 130
5x . ( 1 + 52 ) = 130
5x . 26 = 130
5x = 130 : 26
5x = 5
=> x = 1
a, \(390-\left(x-7\right)=13^2:12\)
\(390-\left(x-7\right)=\) \(\dfrac{169}{12}\)
\(x-7=390-\dfrac{169}{12}\)
\(x-7=\dfrac{4511}{12}\)
\(x=\dfrac{4511}{12}+7\)
\(x=\dfrac{4595}{12}\)
Vậy ...
b, \(\left(x-35.2^2\right):7=3^3-24\)
\(\left(x-35.4\right):7=27-24\)
\(\left(x-140\right):7=3\)
\(\Leftrightarrow\left(x-140\right)=3.7\)
\(\Leftrightarrow x-140=21\)
\(\Leftrightarrow x=161\)
Vậy .....
c) \(x-6:2-\left(4^2.3-24\right):2:6=3\)
\(x-3-\left(16.3-24\right):2:6=3\)
\(x-3-\left(48-24\right):2:6=3\)
\(x-3-24:2:6=3\)
\(x-3-2=3\)
\(x=3+2+3\)
\(x=8\)
Vậy ......
d) \(4x-5=5+5^2+5^3+.....+5^{99}\)
Đặt :
\(A=5+5^2+.........+5^{99}\)
\(\Leftrightarrow5A=5^2+5^3+..........+5^{100}\)
\(\Leftrightarrow5A-A=\left(5^2+5^3+......+5^{100}\right)-\left(5+5^2+....+5^{99}\right)\)
\(\Leftrightarrow4A=5^{100}-5\)
\(\Leftrightarrow A=\dfrac{5^{100}-5}{4}\)
\(\Leftrightarrow4x+5=\dfrac{5^{100}-5}{4}\)
Đến đây thì sao nữa nhỉ ?
e) \(\left(2x-1\right)^4=625\)
\(\Leftrightarrow\left[{}\begin{matrix}\left(2x-1\right)^4=5\\\left(2x-1\right)^4=-5\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}2x-1=5\\2x-1=-5\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=3\\x=-2\end{matrix}\right.\)
Vậy ....
a) 3x = 27 (Áp dụng: ax = an (a > 1) => x = n)
3x = 33
x = 3
Vậy x bằng 3
b) 52x = 125 (Áp dụng: ax = an (a > 1) => x = n)
52x = 53
2x = 3
x = 3 : 2
x = 3/2
Vậy x bằng 3/2
c) 4x . 42 = 64
4x . 16 = 43
4x = 43 : 16
4x = 4
x = 1
Vậy x bằng 1
d) 32x : 3 =27
32x : 3 = 33
32x = 33 : 3
32x = 9
32x = 32
2x = 2
x = 1
Vậy x bằng 1
* P/s: Sai cho mình xin lỗi ạ *
Học tốt ~~
a, (\(\frac{1}{2}\))x = \(\frac{1}{64}\)
<=> (\(\frac{1}{2}\))x = (\(\frac{1}{2}\))6
<=> x = 6
b, 35 :3x = 9
<=> 35 :3x = 32
<=> 3x = 35 :32
<=> 3x = 33
<=> x = 3
Chúc bạn học tốt
a) (x - 3)2 - 1 = 24
(x - 3)2 = 24 + 1
(x - 3)2 = 25
(x - 3)2 = (\(\pm\) 5)2
TH1 : (x - 3)2 = 52
x - 3 = 5
x = 5 + 3
x = 8
TH2 : (x - 3)2 = (-5)2
x - 3 = -5
x = -5 + 3
x = -2
vậy x ϵ {8;-2}