\(5^{2x-3}\)=125
(2x-1)3=125 (2x-1)5=x5
\(\left(2x-1\right)^3=125\)
\(\Leftrightarrow\left(2x-1\right)^3=5^3\)
\(\Leftrightarrow2x-1=5\Leftrightarrow x=3\)
\(------\)
\(\left(2x-1\right)^5=x^5\)
\(\Leftrightarrow2x-1=x\)
\(\Leftrightarrow x=1\)
a) 5^x=125
b)3^2x=81
c)5^2x-3-2*5^2=5^2*3
a)5^x=125
125=5^3
5^x=5^3
=>x=3
b)3^2x=81
81=3^4
3^2x=3^4
=>2x=4
x=4:2
x=2
3
Bài 3:
c) 5 mũ x + 3 = 125 d) 2 mũ 2x + 3 + 2 mũ 2x + 1
a)5x+3 = 125
5x+3 = 53
x = 3 - 3 = 0
em cần làm gì với ý d
Tìm x
a) 5^x=125
b)3^2x=81
c)5^2x-3-2*5 = 5^2 *3
5x=125
=>5xx=53
=> x=3
Vậy x=3
32x=81
=>32x=34
=>2x=4
=>x=4:2=2
Vậy x=2
Tk mk
a, => 5^x = 5^3
=> x = 3
b, => 3^2x = 3^4
=> 2x = 4
=> x = 2
Tk mk nha
a,5x=125
5x=53
=>x=3
b,32x=81
32x = 34
=>. 2x = 4
=> x = 4 : 2
=> x = 2
~~ học tốt ~~
(2\(x\) - 1)3 = 125
(2\(x\) - 1)3 = 53
2\(x\) - 1 = 5
2\(x\) = 6
\(x\) = 3
(2\(x\) - 1)5 = \(x^5\)
2\(x\) - 1 = \(x\)
2\(x\) - \(x\) = 1
\(x\) = 1
2\(x^5\) + 2 = 4
2\(x^5\) = 4 - 2
2\(x^5\) = 2
\(x^5\) = 1
\(x\) = 1
a)42x - 6 = 1
b)2x-1= 16
c)5<5x<125
d)5x+1= 125
e)52x-3 - 2. 52 = 52 . 3
\(a,4^{2x-6}=1\)\(\Leftrightarrow2x-6=0\Leftrightarrow2x=6\Rightarrow x=3\)
\(b,2^{2x-1}=16\Rightarrow2^{2x-1}=2^4\)
\(\Rightarrow2x-1=4\Rightarrow2x=5\Rightarrow x=\frac{5}{2}\)
\(c,5< 5^x< 125\Rightarrow5^1< 5^x< 5^3\)\(\Rightarrow1< x< 3\)
\(d,5^{x+1}=125\Rightarrow5^{x+1}=5^3\Rightarrow x+1=3\Rightarrow x=2\)
\(a,4^{2x-6}=1\)
\(4^{2x-6}=4^0\)
\(\Rightarrow2x-6=0\)
\(\Rightarrow2x=6\Leftrightarrow x=3\)
\(b,2^{x-1}=16\)
\(2^{x-1}=2^4\)
\(\Rightarrow x-1=4\)
\(\Rightarrow x=5\)
a)4^2x-6=1=>4^2x-6=1=4^0 b)2^x-1=16=2^4 c) 5=5^1<5^x<125=5^3 d)5^x+1=125=5^3
=>2x-6=0=>2x=6=>x=3 =>x-1=4=>x=5 =>x=2 => x+1=3=>x=2
e)=>5^2x-3-50=75
=>5^2x-3=25=5^2
=>2x-3=2
=>2x=5=>x=5/2
5 mũ 2x+3+25.5 (5 mũ x )tất cả mũ=125 mũ 3 :5 mũ 2
(5 mũ 2)mũ 3 : 5 mũ 2
5 mũ 2 x3 :5 mũ 2
5 mũ 6 : 5 mũ 2 =5 mũ 4=625
3) Tìm x của N biết a) 80 - ( 2 + 2x ) : 2 = 40 b) 11^2 - 121 = 0 c) 5^x+3 - 7 × 5^2 = 5^2 × 18 d) x^10 = x e) x^10 = 1^x g) ( 2x - 15 )^5 = ( 2x - 15 )^3 4) Thực hiện phép tính a) 5^3 ÷ 5^2 + 2^2 × 3 b) 4^3 × 125 - 125 ÷ 5^2 c) 6^2 × 28 + 72 × 6^2 d) 5^6 ÷ 5^4 + 3 × 3^2 - 80 e) 2^3 × 19 - 2^3 × 14 × 1^2021
(|2x-5|+1).(x^3-125)=0
a, 2x . 4 = 128
b, x15 = x 1
c, (2x + 1)3 = 125
d, (x – 5)4 = (x - 5)6
e, x10 = x
f, (2x -15)5 = (2x -15)3
a) 2x . 4 = 128
<=> 2x = 32
<=> 2x = 25
<=> x = 5
b) x15 = x1
<=> x15 - x = 0
<=> x(x14 - 1) = 0
<=> \(\orbr{\begin{cases}x=0\\x^{14}-1=0\end{cases}}\Leftrightarrow\orbr{\begin{cases}x=0\\x^{14}=1^{14}\end{cases}}\Leftrightarrow\orbr{\begin{cases}x=0\\x=\pm1\end{cases}}\)
c) (2x + 1)3 = 125
<=> (2x + 1)3 = 53
<=> 2x + 1 = 5
<=> 2x = 4
<=> x = 2
d) (x - 5)4 = (x - 5)6
<=> (x - 5)6 - (x - 5)4 = 0
<=> (x - 5)4[(x - 5)2 - 1] = 0
<=> \(\orbr{\begin{cases}\left(x-5\right)^4=0\\\left(x-5\right)^2-1=0\end{cases}}\)
Khi (x - 5)4 = 0 => x - 5 = 0 => x = 5
Khi (x - 5)2 - 1 = 0 <=> (x - 5)2 = 12 <=> \(\orbr{\begin{cases}x-5=1\\x-5=-1\end{cases}}\Leftrightarrow\orbr{\begin{cases}x=6\\x=4\end{cases}}\)
a, 2x . 4 = 128
=> 2x = 128 : 4 = 32
=> x = 32 : 2 = 16
Vậy x = 16
b, x15 = x 1 => Sai đề
c, (2x + 1)3 = 125
=> ( 2x + 1 ) = 53
=> 2x + 1 = 5
=> 2x = 5 - 1
=> 2x = 4
=> x = 4 : 2
=> x = 2