Question

Arătați ca numarul 3la 72plus2ori 3la 73 plus 3la 74 este pătrat perfect

Answer 1

${3}^{72} + 2 \times {3}^{73} + {3}^{74}$

$= {3}^{72} (1 + 2 \times 3 + {3}^{2} )$

$= {3}^{72} (1 + 6 + 9)$

$= {3}^{72} \times 16$

$= { ({3}^{36}) }^{2} \times {4}^{2}$

$= {( {3}^{36} \times 4) }^{2} = > p.p$