X 1 3 x 9 12 x 2 6 x 1 4 July 8, 2019 16 32 64 128 ( 6 x − 1 ) ⋅ ( 6 x + 1 ) − 4 x ⋅ ( 9 x + 3 ) = − 4 1 3 x − 1 + 9 x + 1 2 − 3 x + 3 + 3 3 x − 9 ≥ 3 x + 1 - 6/(x ^ 2 - 9) - (x + 1)/(x - 3) = 1/(x + 3)
