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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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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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