Răspuns :
1.
[tex]\it 5^{n-4}=25^{36} \Rightarrow 5^{n-4}=(5^2)^{36} \Rightarrow 5^{n-4}=5^{72} \Rightarrow n-4=72|_{+4} \Rightarrow n=76[/tex]
2.
[tex]\it \left.\begin{aligned} \it x=3y\\ \\ \it y=6z\end{aligned}\right\} \Rightarrow x=3\cdot6z \Rightarrow x=18z \Rightarrow \dfrac{x}{z}=18[/tex]
Răspuns:
Explicație pas cu pas:
1) 5ⁿ⁻⁴ = 25³⁶ <=> 5ⁿ⁻⁴ = (5²)³⁶ <=>
5ⁿ⁻⁴ = 5²ˣ³⁶ => n-4 = 72 => n = 72+4 => n = 76
2) x = 3y ; y = 6z ; z ∈ R* ; x/z = ?
x = 3·6z = 18z => x/z = 18z/z => x/z = 18
3) (-1)²⁰¹⁸-(-1)²⁰¹⁷-0²⁰²⁰ = 1-(-1)-0 = 1+1 = 2
4) √(9/4) ; 1,(6) : (8/5)
√(9/4) = 3/2
1,(6) : (8/5) = (16-1)/9 : (8/5) = 15/9 · 5/8 = 5/3 ·5/8 = 25/24
25/24 < 3/2 => nu este scris in ordine crescatoare