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
User manual Casio FX-991EX (English - 46 pages)
User manual Casio FX-991EX (English - 46 pages)
Casio fx-991EX Classwiz for High School Students: Getling, David: 9781548247102: Amazon.com: Books