Solution - Simplification or other simple results

Step  1  :

 1.1     28 = 22•7

(28)² = (2²•7)² = 2⁴ • 7²

Equation at the end of step  1  :

  (722) +  (24•72)

Step  2  :

 2.1     72 = 23•32

(72)² = (2³•3²)² = 2⁶ • 3⁴

Equation at the end of step  2  :

  (26•34) +  (24•72)

Step  3  :

Final result :

  5968