If \(2 \cdot 4^{2 k+1}+3^{3 k+1}=11 t\) and \(2 \cdot 4^{2 k+3}+3^{3 k+4}=11\) \(\left(p t+3^q\right)\),…

If \(2 \cdot 4^{2 k+1}+3^{3 k+1}=11 t\) and \(2 \cdot 4^{2 k+3}+3^{3 k+4}=11\) \(\left(p t+3^q\right)\), where \(k, t \in Z^{+}\), then \((p, q)=\)
  1. \((16,3 k+1)\)
  2. \((16,3 k+4)\)
  3. \((32,3 k+1)\)
  4. \((32,3 k+4)\)

Solution

By verification method, if \(k=0\) Then, \(2 \cdot 4^1+3^1=11 t\) \(\Rightarrow \quad 8+3=11 t \Rightarrow t=1\) Now, from the second given relation on putting the values of \((k, t)=(0,1)\), we get \(\begin{aligned} 2 \cdot(64)+81 & =11\left(p+3^q\right) \\ \Rightarrow \quad 128+81 & =11\left(p+3^4\right) \\ \Rightarrow \quad 11\left(p+3^q\right) & =209 \Rightarrow p+3^q=19 \end{aligned}\) Now, from the option \(p\) must be 16 and \(q=1\) \(=(3 k+1)_{k=0} .\) Hence, option (a) is correct.

Asked in: AP EAMCET 2019 (23 Apr Shift 1)

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