![Casio fx-991EX keeps giving math error for simple calculations like ((1/2)/2) and sin inverse (10) etc. Any idea on how to fix this? Is there a chance that the calculator may be Casio fx-991EX keeps giving math error for simple calculations like ((1/2)/2) and sin inverse (10) etc. Any idea on how to fix this? Is there a chance that the calculator may be](https://preview.redd.it/c3y0lcx0ody81.jpg?width=3000&format=pjpg&auto=webp&s=fbeca87556aad36f1c967016c1ccee9a5c323cf9)
Casio fx-991EX keeps giving math error for simple calculations like ((1/2)/2) and sin inverse (10) etc. Any idea on how to fix this? Is there a chance that the calculator may be
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Calculatrice scientifique Casio FX 92+ (CY295) - calculatrice spéciale Collège Pas Cher | Bureau Vallée
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