Here's the correct solution:
Original expression: (a^5 - (1/3)a^3 - 5a) - (3/4)a^5 - (1/2)a^4 - 6a
Distribute the negative sign: = a^5 - (1/3)a^3 - 5a - (3/4)a^5 + (1/2)a^4 + 6a
Now, combine like terms: = (a^5 - (3/4)a^5) - (1/3)a^3 + (1/2)a^4 - 5a + 6a
= (1/4)a^5 - (1/3)a^3 + (1/2)a^4 + a
So, the correct solution is: (1/4)a^5 - (1/3)a^3 + (1/2)a^4 + a