Question

(2n - 3)^2 = 9

(n+5)^3 = -64

Tìm n

Answer 1

a, \(\left(2n-3\right)^2=9\)

\(\left(2n-3\right)^2=3^2\)

TH1 : \(2n-3=3\)

\(2n=6\)

n \(=3\)

TH 2 : \(2n-3=-3\)

\(2n=0\)

\(n=0\)

Vậy \(n\in\left\{0;3\right\}\)

Answer 2

\(\left(n+5\right)^3=-64\)

\(\Rightarrow\)\(\left(n+5\right)^3=\left(-4\right)^3\)

\(\Rightarrow\)\(n+5=-4\)

\(\Rightarrow n=-4-5\)

\(\Rightarrow n=-9\)

~~~Hok tốt ~~~