Question

Tìm x:

1)\(\left(x-2\right)^3=-27\)

2)\(\left(2x-3\right)^2=25\)

3)\(3^{x-1}=\dfrac{1}{243}\)

4)\(2x+2^{x+3}=144\)

5)\(\left(2x-3\right)^2=16\)

6)\(\left(3x-2\right)^5=-243\)

7)\(\left(7x+2\right)^{-1}=3^{-2}\)

Chứng Minh Rằng

\(3^{n+3}+3^{n+1}+2^{n+3}+2^{n+2}⋮6\)

Giúp mình với

Answer 1

Tìm x dễ tự làm:

\(3^{n+3}+3^{n+1}+2^{n+3}+2^{n+2}\)

\(=3^n.3^3+3^n.3^1+2^n.2^3+2^n.2^2\)

\(=3^n.9+3^n.3+2^n.8+2^n.4\)

\(=3^n\left(9+3\right)+2^n\left(8+4\right)\)

\(=3^n.12+2^n.12\)

\(=12\left(3^n+2^n\right)\)

\(=6.2\left(3^n+2^n\right)⋮6\rightarrowđpcm\)

Answer 2

https://hoc24.vn/hoi-dap/question/462129.html?pos=1207827

vào link này làm hộ mik bài 3 nha