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
\(a.\)\(5^x=125\)
\(5^x=5^3\Rightarrow x=3\)
\(b.\)\(x^3=64\)
\(x^3=4^3\Rightarrow x=4\)
\(c.\)\(\left(x-1\right)^2=25\)
\(x^2=5^2\)mà \(\left(x-1\right)\)nên \(x=5+1=6\)
P/s: Ý d thiếu nhé bạn
a)5x=125
5x=53
=>x=3
b)tương tụ câu a
c)(x-1)2=25
(x-1)2=52
=>x-1=5
x=5+1
x=6
d)thiếu đề!
Dễ dàng thôi bạn ạ!
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
<=> 5x=51
<=> x=1.