Question

[Heo Con🐷🐷🐷]

Tìm số tự nhiên x, sao cho:

a) (x+1)^3 : (x+1)=4

b) 3^x+60=87

c) 6×2^x+3×2^x= 9×29

d) 2^x-64=2^6

Giúp em với ạ!

Answer 1

[Phạm Băng Nguyệt]

a, \(\left(x+1\right)^3:\left(x+1\right)=4\)

\(\Leftrightarrow\left(x+1\right)^2=4\)

\(\Leftrightarrow\left(x+1\right)^2=2^2\)

\(\Leftrightarrow\left[{}\begin{matrix}x+1=2\\x+1=-2\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=1\\x=-3\end{matrix}\right.\)

Vậy .....

b, \(3^x+60=87\)

\(\Leftrightarrow3^x=87-60\)

\(\Leftrightarrow3^x=27\)

\(\Leftrightarrow3^x=3^3\)

\(\Leftrightarrow x=3\)

Vậy ...

c, (Viết cái đề khó nhìn quá à)

d, \(2^x-64=2^6\)

\(\Leftrightarrow2^x-64=64\)

\(\Leftrightarrow2^x=64+64\)

\(\Leftrightarrow2^x=128\)

\(\Leftrightarrow2^x=2^7\)

\(\Leftrightarrow x=7\)

Vậy ...

Answer 2

[Heo Con🐷🐷🐷]

Cảm ơn ạ