a) 3-2 . 34 . 3n = 37
=> 3-2+4+n = 37
=> 32+n = 37
=> 2 + n = 7
=> n = 5
Vậy n = 5
a) 3-2. 34.3n = 37
3-2 + 4 + n = 37
32 + n = 37
2 + n = 7
n = 5
Vậy n = 5
b) 2-1.2n + 4.2n = 9.25
2n(2-1 + 4) = 9.25
2n. \(\frac{9}{2}\) = 9.25
2n = 9.25 : \(\frac{9}{2}\)
2n = 64
2n = 26
n = 6
Vậy n = 6
c) 32 < 2n < 128
25 < 2n < 27
5 < n < 7
=> n = 6
Vậy n = 6
d) 44 \(\leq \) 4n \(\leq \) 4096
44 \(\leq \) 4n \(\leq \) 46
4 \(\leq \) n \(\leq \) 6
=> n = 5
Vậy n = 5
mk ko chắc câu d nhé
4
b) 2-1 . 2n + 4 . 2n = 9 . 25
=> \(\dfrac{1}{2}\) . 2n + 4 . 2n =9 . 25
=> \(\left(\dfrac{1}{2}+4\right)\) . 2n = 9. 25
=> \(\dfrac{9}{2}\) . 2n = 9 . 25
=> 2n = 9 . 25 . \(\dfrac{9}{2}\)
=> 2n = 26
=> n = 6
Vậy n = 6
d) \(n \epsilon \left \{ 4;5;6 \right \}\)
Vậy \(n \epsilon \left \{ 4;5;6 \right \}\)
4 \(\leq \) n \(\leq \) 6
pn ghi xong khúc này rồi thêm cái mk mới post nha
\(a\)) \(3^{-2}.3^4.3^n=3^7\)
=> \(3^{-2.4.n}=3^7\)
=> \(3^{2-n}=3^7\)
=> \(2-n=7\)
=> \(n=-5\)
Vậy \(n=-5\)
