help me please thanks in advance

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From up to down ;
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The first box :
[tex]f(n) = 3. ({2})^{n - 1} [/tex]
The second box :
[tex]f(n) = 2. ({4})^{n - 1} [/tex]
The third box :
[tex]f(n) = 2. ({6})^{n - 1} [/tex]
♥️♥️♥️♥️♥️♥️♥️♥️♥️♥️♥️♥️♥️♥️