Simplify

3/a-4 + 2/a+3 -21/a²-a-12

3 answers

3/a - 4 + 2/a + 3 - 21/a^2 - a - 12

Combine like terms:

(3 + 2) / a - (4 + 3) - 21 / a^2 - a - 12
5 / a - 7 - 21 / a^2 - a - 12

Therefore, the simplified expression is:

5 / a - a - 21 / a^2 - 19
as usual, the user's carelessness with parentheses made you mess up -- though it should have been easy to figure it out. Clearly the user meant

3/(a-4) + 2/(a+3) - 21/(a²-a-12) = 5/(a+3)
Apologies for the oversight. Thank you for pointing that out. The correct simplification of the expression is:

3/(a-4) + 2/(a+3) - 21/(a²-a-12) = 5/(a+3)