There is a problem with the calculator where equivalent statements when entered differently will lead to different results.

Earlier when entering in -9^2 when calculating for an integral, I got a wrong answer. Its not until I answered in the equivalent 81 that the true answer showed up. This inspite of -9 to the second power being the exact same as 81.

To investigate further, I typed in -9^2 into the scientific calculator and got -81…despite the fact that any negative integer squared is positive.

The correct answer does come out if I type in (-9)^2 however. So it can parse if one is specific in their notation using brackets.

If the calculator outputs the wrong sign like this, its no wonder my integral was off.