• Avoid dropping your calculator and otherwise subjecting it to strong impact. • Do not store the calculator or leave it in areas exposed to high temperature or humidity, or large amounts of dust. When exposed to low temperatures, the calculator may require more time to display results and may even fail to operate.
fully reread this manual and ensure that the problem is not due to low battery power (fx-85B/fx-280) or operational error. • The contents of this manual are subject to change without notice. • No part of this manual may be reproduced in any form without the express written consent of the manufacturer.
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Note! • A mode guide is located at the top of the display screen. • DEG, RAD, and GRA modes can be used in combination with COMP and SD modes. • does not exit SD mode. • exits SD mode. •...
• Example 7: 4/3π5 - A x - Constant Calculations • Press make that number a constant. • “K” is on the display while a constant is being used. • Use the COMP mode for constant calculations. • Example 1: 2.3 3, then 2.3 6 (2.3 3) (2.3 6) •...
• Example 4: 1.7 (1.7 (1.7 (1.7 Memory Calculations • Use the COMP mode for memory calculations. • Use replaces current memory contents. • “M” appears when there is a value in memory. • To clear memory, press • Example 1: (53 6) (23 8) (56 2) (99Ö4) 210.75 (53 6) (23 8) (56 2)
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• Example 3: To calculate the following using memory and a constant: (12 3) (45 3) (78 3) 135. (12 3) (45 3) (78 3) (Memory recall) kAdditional fx-85B/fx-280 Memory Calculations • The fx-85B/fx-280 has two additional memories named A and B.
• Example 2: To store the results of 123 Fraction Calculations • Use COMP mode for fraction calculations. • Total number of digits (including division marks) cannot exceed 10. • Example 1: • Example 2: 3 • Example 3: • Example 4: Fraction/decimal calculation result is always decimal.
• Example 5: • Example 6: 1 Percentage Calculations • Use COMP mode for percentage calculations. • Example 1: To calculate 12% of 1500. • Example 2: To calculate what percentage of 880 is 660. • Example 3: To add 15% onto 2500. ↔...
• Example 4: To discount 3500 by 25%. • Example 5: To calculate the following using a constant. 12% of 1200 = 144 18% of 1200 = 216 23% of 1200 = 276 (12%) (18%) (23%) Scientific Function Calculations • Use COMP mode for scientific function calculations. •...
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• Example 2: 1°2’3” + 4.56 = 5.594166667 • Example 3: sin 87°65’43.21” = 0.999447513 (DEG mode) • Example 4: 1.23↔ 1°13’48” • Example 5: 12°34’ ↔ 12.56666667 You can also use tween sexagesimal and decimal. kTrigonometric/Inverse Trigonometric Functions • Example 1: sin ( 4.56 43.21 I A O...
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• Example 2: cos 63°52’41” (DEG mode) • Example 3: tan ( 35gra)(GRA mode) • Example 4: cos • Example 5: To convert 45 degrees to radians, grads, and back to degrees. Repeated conversion between angle units can cause nor- mally minute error to accumulate, resulting in poor preci- sion.
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kHyperbolic/Inverse Hyperbolic Functions • Example 1: sinh 3.6 • Example 2: sinh kCommon and Natural Logarithms, Exponents • Example 1: log 1.23 • Example 2: In 90 ( log Iog 64 • Example 3: Iog 4 • Example 4: 10 •...
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• Example 8: log sin 40° + log cos 35° (DEG mode) S R + To convert to antilogarithm: • Example 9: 8 k Square Roots, Cube Roots, Squares, Reciprocals and Factorials • Example 1: 2 A L + • Example 2: A D + •...
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• Example 5: 8! kFIX, SCI, NORM, RND, RAN#, ENG Calculations • Example 1: 1.234 1.234, rounding result to two places (FIX 2). • Example 2: 1.234 1.234, rounding input to two places. F 7 2 • Press • Example 3: 1Ö 3 , displaying result with two significant digits (SCI 2).
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• Example 4: To convert 56,088 meters to kilometers. • Example 5: To convert 0.08125 grams to milligrams. • Example 6: To generate a random number between 0.000 and 0.999. Example (results differ each time) kCoordinate Conversion • Example 1: To convert polar coordinates (r 2, rectangular coordinates (x, y).
θ kPermutation • Example: To determine how many different 4-digit values can be produced using the numbers 1 through 7. kCombination • Example: To determine how many different 4-member groups can be organized in a group of 10 individuals. Statistical Calculations (SD Mode) •...
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Input Data. Sample standard deviation Population standard deviation Arithmetic mean Number of data Sum of values Sum of squares of values • inputs the same data twice (as above). • You can also input multiple entries of the same data using .
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kMaking Corrections During Data Input • Example 1: To change data you have just input. Correct Actual • Example 2: To change data you previously input. Correct Actual 31 } — 20 — Correction Correction...
Technical Information kKeys and Their Functions • General Arithmetic calculations ... +, ,, -, ... \, = Backspace ... Q Clear(retains memory) ... k Number input ... 0 – 9, l Power on; All clear ... t Sign change ... E •...
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Memory B store ... A J 2 Memory M store ... A J 3 • Special Display/memory swap ... A N, Exponent ... e Internal rounding ... A b Parentheses ... O, P Pi (3.1415926536) ... A x Select mode ... F Sexagesimal ...
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Cube ... A N Cube root ... A D Engineering ... A J, Factorial ... A f Fraction ... C Fraction ... A B Hyperbolic ... M Natural antilogarithm ... A U Natural logarithm ... T Percent ... A v Polar-to-rectangular ...
Sum of squares of values ... A a Sum of values ... A o kExponential Display Formats This calculator can display up to 10 digits. Larger values are automatically displayed using exponential notation. In the case of decimal value, you can select between two formats that determine at what point exponential notation is used.
To switch between NORM 1 and NORM 2 Press . There is no indication on the display of which format is currently in effect, but you can determine the setting by performing the following calculation. • All of the examples in this manual show calculation results using the NORM 1 format.
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• In a series of calculations, press result is displayed to clear only the last calculation per- formed. • To change the operator key ( etc.) you just pressed, simply press the correct operator key. In this case, the operator of the last key you press is used, but the operation retains the order of precedence of the operation for the first key you pressed.
If this happens, move to an area with more light. • fx-85B/fx-280 This calculator is powered by the CASIO TWO- WAY POWER system, which makes it possible for the calculator to operate even in total darkness.
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Old batteries may leak, causing serious damage to the interior of the calculator. • The battery that comes with the calculator when you pur- chase it is for testing only. It may not provide full service life.
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5. Press to turn power on. kOrder of Operations and Levels Operations are performed in the following order of prec- edence. 1. Functions 2. x , R →P, P →R, nPr, nCr • Operations with the same precedence are performed from left to right, with operations enclosed in parentheses per- formed first.
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Ranges, and Conventions The following are the formulas, ranges, and conventions that are applied to various calculations that can be performed using this calculator. Coordinate Transformation • With polar coordinates, θ can be calculated within a range of –180° θ...
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Permutation • Input range: n • Formula: nPr Combination • Input range: n • Formula: nCr Population Standard Deviation (xi – x) Sample Standard Deviation n – Arithmetic Mean 0 (n, r : integers) (n r)! 0 (n, r : integers) n!(n r)! –...
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Power Supply : fx-82SOLAR/fx-260SOLAR : Solar cell fx-85B/fx-280 : CASIO TWO-WAY POWER System: solar Battery Life (fx-85B/fx-280) : Input Ranges : Functions (DEG) x 9 10 sinx (RAD) x 5 10 cosx (GRA) x 1 10 tanx –1 –1 x ...
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Functions x 1 tanh –1 logx/lnx –1 –1 x 1 x 2.154434690 x 1 x 1 n 1 10 nPr/nCr (n and r are integers) R→P (DEG) P→R (RAD) (GRA) Input and Results Total of hour, minutes, and seconds digits must be 10 or fewer (including separator °’...
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Functions x 0: –1 10 x 0: y However: –1 10 x 0:y ≠ 0 –1 10 x 0: y However: –1 10 Total of integer, numerator, and denominator must be 10 digits or less(including division marks).
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Operating Temperature: 0°C–40°C (32°F–104°F) Dimensions: fx-82SOLAR/fx-260SOLAR: 8(H)i66.5(W)i125(D) mm 5/16"(H)i2-5/8"(W)i4-15/16"(D) fx-85B/fx-280: 13.5(H)i73(W)i144.5(D) mm 1/2"(H)i2-7/8"(W)i5-5/8"(D) Weight: fx-82SOLAR/fx-260SOLAR: 47 g (1.7oz) fx-85B/fx-280: 67 g (2.4oz) including battery Calculation Capacity: • Input/ Basic Calculations 10-digit mantissa; or 10-digit mantissa plus 2-digit expo- ±99 nent up to 10 —...
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CASIO COMPUTER CO., LTD. 6-2, Hon-machi 1-chome, Shibuya-ku, Tokyo 151-8543, Japan SA9709-C Printed in China Imprimé en Chine...
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