Solution - Simplification or other simple results

Reformatting the input :

Changes made to your input should not affect the solution:

 (1): "a3"   was replaced by   "a^3". 

Step  1  :

Equation at the end of step  1  :

  3a3 • a

Step  2  :

Multiplying exponential expressions :

 2.1    a³ multiplied by a¹ = a^{(3 + 1)} = a⁴

Final result :

  3a4