Question

tìm n thuộc N biết:

1) 3^n.2^n=36

2) 25^2n:5^n=125^2

 

Answer 1

mik đang cần gấp

 

Answer 2

1: \(\Leftrightarrow6^n=36\)

=>n=2

2: \(\Rightarrow5^{4n}:5^n=5^6\)

=>3n=6

hay n=2

Answer 3

`3^n. 2^n = 36`

`<=> 2^n.3^n = 2^2 . 3^2`

`<=> n=2`

___________________________

`25^(2n) : 5^n = 125^2`

`<=>5^2^(2n) : 5^n = 125^2`

`<=> 5^(4n) : 5^n = 125^2`

`<=> 5^3n = 5^6`

`<=> `3n=6`

`<=> n = 6 : 3`

`<=> n = 2`