fx-82SOLAR fx-85B fx-260SOLAR fx-280

fx-82SOLAR/ fx-260SOLAR

fx-85B/fx-280

ENGLISH ESPAOL FRANAIS

DEUTSCH 110 ITALIANO 147
CASIO ELECTRONICS CO., LTD. Unit 6, 1000 North Circular Road, London NW2 7JD, U.K.

Contents

Handling Precautions 2 Modes 3 Basic Calculations 5 Constant Calculations 6 Memory Calculations 7 Fraction Calculations 9 Percentage Calculations 10 Scientific Function Calculations 11 Statistical Calculations (SD Mode) 18 Technical Information 21 1

Handling Precautions

Your calculator is made up of precision components. Never try to take it apart. 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. Correct operation will resume once the calculator is brought back to normal temperature. The display will go blank and keys will not operate during calculations. When you are operating the keyboard, be sure to watch the display to make sure that all your key operations are being performed correctly. Never leave the dead battery (fx-85B/fx-280) in the battery compartment. It can leak and damage the unit. Avoid using volatile liquids such as thinner or benzine to clean the unit. Wipe it with a soft cloth, or with a cloth that has been dipped in a solution of water and a neutral detergent and wring out. In no event will the manufacturer and its suppliers be liable to you or any other person for any damages, expenses, lost profits, lost savings, or any other damages arising out of malfunction, repairs, or battery replacement (fx-85B/fx280), or insufficient light. The user should prepare physical records of data to protect against such data loss. Never dispose of battery (fx-85B/fx-280), the liquid crystal panel, or other components by burning them. Before assuming malfunction of the unit, be sure to care2
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. Keep this manual on hand for future reference.

Application

Standard deviation calculations Normal calculations Calculations using degrees Calculations using radians Calculations using grads Number of decimal place specification Number of significant digit specification Cancels FIX and SCI settings Key Operation Mode Name* SD COMP DEG RAD GRA FIX SCI NORM

Fl F0 F4 F5 F6 F7 F8 F9

* Display indicators show current mode setting. Absence of display indicator indicates COMP Mode. 3
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. F9 does not exit SD mode. F0 exits SD mode. F0 does not clear SCI or FIX specifications. Always press t before entering DEG, RAD, and GRA modes. Remember to always set the operating mode and angular unit (DEG, RAD, GRA) before starting your calculation.

Basic Calculations

Use the COMP mode for basic calculations. Example 1: 234.+ 4.5 , 53 = Example 2: 56(12)(2.5) 56 - 12 E \ 2.5 E = Example 3: 23(11020) 2 \ 3 -1 e 20 = 6.66666666719 Example 4: 7845=36 7-8,4-5= Example 5: 6 =0.4-5 \6AN =

Example 6: 2[76(54)]122 2-O7+6-

O 5+ 4PP =

You can skip all P operations before the = key. 5
Example 7: 4/353 4\3 -Ax- 5AN =

523.5987756

Constant Calculations
Press + , , , - or \ twice after inputting a number to 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: 2.33, then 2.36

(2.33) (2.36)

2.3 + + 3 = 6=

5.3 8.3

Example 2: 122.3, then 12(9)

(122.3) (12(9))

12 - - 2.3 = 9E=

27.6 108.

Example 3: 1717171768
(1717) (171717) (17171717)

17 + + =

34. 51. 68.

Example 4: 1.748.3521

(1.7 2) (1.7 )

1.7 - - =

2.89 4.913 8.3521

(1.7 4)

Memory Calculations
Use the COMP mode for memory calculations. Use A Y, |, A { and Z for memory calculations. A Y replaces current memory contents. M appears when there is a value in memory. To clear memory, press 0 A Y or t A Y. Example 1: (536)(238)(562)(994)210.75
(536) (238) (562) (994) (Memory recall)
53 + 6 = A Y 23 , 8 | 56 - 2 | 99 \ 4 |

M M M M M

59. 15. 112. 24.75 210.75
Example 2: To calculate the following using memory as shown.
Example 3: To calculate the following using memory and a constant: (123)(453)(783)135.
(123) (453) (783) (Memory recall)
3 - - 12 = A Y 45 A { 78 |

MK MK MK MK

36. 135. 234. 135.
kAdditional fx-85B/fx-280 Memory Calculations
The fx-85B/fx-280 has two additional memories named A and B. Use A J to store data and 0 to recall data. Storing data in a memory replaces anything stored there previously. To clear a memory, store a zero in it. Example 1: To input 123 in memory A.

t 123 A J 1

Example 2: To store the results of in memory B.

t 123 - 456 A J 2 t02

56088. 56088.

Fraction Calculations

Use COMP mode for fraction calculations. Total number of digits (including division marks) cannot exceed 10. 7 Example 1: 7 15. 2C3+4C5= Example 2: 12 3C1C4+ 1C2C3= Example 3: 2C4

12. 2 4. 1 2.

Example 4: 1 1.62.1 C 2 + 1.6 =
Fraction/decimal calculation result is always decimal. 9

Example 5:

1 0.5(Fraction Decimal) 2 1C2=

1 2. 0.2.

Example 6: 3 1C 2C 3

3. 5 3. 3.

Percentage Calculations
Use COMP mode for percentage calculations. Example 1: To calculate 12% of 1500. 1500 - 12 A v
Example 2: To calculate what percentage of 880 is 660. 660 \ 880 A v Example 3: To add 15% onto 2500. 2500 - 15 A v + 10

Example 4: To discount 3500 by 25%. 3500 - 25 A v ,
Example 5: To calculate the following using a constant. 12% of 1200 = 144 18% of 1200 = 216 23% of 1200 = 276

(12%) (18%) (23%)

1200 - - 12 A v 18 A v 23 A v

144. 216. 276.

Scientific Function Calculations
Use COMP mode for scientific function calculations. Some calculations may take a long time to complete. Wait for result before starting next calculation. =3.1415926536.

kSexagesimal Functions

Example 1: 142536 + 122334 = I 25 I 36 I + 12 I 23 I 34 I = 11

264910.

Example 2: 123 + 4.56 = 5.I 2 I 3 I + 4.56 =

5.594166667

Example 3: sin 876543.21 = 0.999447513 (DEG mode) 87 I 65 I 43.21 I S Example 4: 1.1.23 I

0.999447513

11348. 1.23 11348.
Example 5: 1234 12.I 34 I A O

12.56666667

You can also use I when inputting values to convert between sexagesimal and decimal.
kTrigonometric/Inverse Trigonometric Functions
Example 1: sin ( rad) (RAD mode) 6

Ax\6=S

Example 2: cos 635241 (DEG mode) 63 I 52 I 41 I W Example 3: tan (35gra)(GRA mode) 35 E h 0.612800788 Example 4: cos1 ( 2 rad) (RAD mode) 2

RAD GRA DEG

0.440283084

2A L\2=A V

0.785398163
Example 5: To convert 45 degrees to radians, grads, and back to degrees.

F 4 45

A F 5 0.785398163 AF6 AF4
Repeated conversion between angle units can cause normally minute error to accumulate, resulting in poor precision. 13
kHyperbolic/Inverse Hyperbolic Functions
Example 1: sinh 3.6 Example 2: sinh3.6 M S 30 M A j

18.28545536 4.094622224

kCommon and Natural Logarithms, Exponents
Example 1: log 1.23 Example 2: In 90 (loge 90) 1.23 R 90 T
0.089905111 4.49980967 3.
Iog 64 Example 3: Iog R \ 4 R = Example 4: 100.e3.4 A Q + 5- 3E AU= Example 5: 23 Example 6: 23 Example 7: e10 2w3= 2w3E= 10 A U
2.760821773 8. 0.125 22026.46579
Example 8: log sin 40 + log cos 35 (DEG mode) 40 S R +35 W R = 0.278567983
To convert to antilogarithm:

A Q 0.526540784

Example 9: 81/3
k Square Roots, Cube Roots, Squares, Reciprocals and Factorials
Example 1: 5 2AL+3 AL- 5A L= Example 2: A D + 27 E A D = 1.290024053 Example 3: + 30 K = 1 Example 4: 3AX, 4A X=

5.287196909

Example 5: 8!

40320.

kFIX, SCI, NORM, RND, RAN#, ENG Calculations
Example 1: 1.2341.234, rounding result to two places (FIX 2).

1.234 +1.234 =

Example 2: 1.2341.234, rounding input to two places.

F 1.234 A b +

1.234 A b = Press F 9 to clear FIX specification. Example 3: , displaying result with two significant digits (SCI 2).
1 \3 = Press F 9 to clear SCI specification.

0.0 00

Example 4: To convert 56,088 meters to kilometers. 56088 A J

56.088 03

Example 5: To convert 0.08125 grams to milligrams.08125 A J

81.2503

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 (r2, 60) to rectangular coordinates (x, y). (DEG mode) x y 2 A z 60 =

1.732050808

A N swaps displayed value with value in memory.
Example 2: To convert rectangular coordinates (1, 3) to polar coordinates (r, ). (RAD mode) r 1Ay 3AL =

A N 1.047197551

kPermutation
Example: To determine how many different 4-digit values can be produced using the numbers 1 through 7. 7Am4=

kCombination

Example: To determine how many different 4-member groups can be organized in a group of 10 individuals. 10 A n 4 =
Statistical Calculations (SD Mode)
Press F l to enter the SD Mode for statistical calculations using standard deviation. If FIX or SCI is on the display, press F 9 first. Data input always starts with A u. Example: To calculate n1, n, o, n, x, and x2 for the following data : 55, 54, 51, 55, 53, 53, 54, 52.

Enter SD Mode.

Input Data.
A u 55 } 54 } 51 } 55 } 53 } }

54 } 52 }

Sample standard deviation

Aq Ap A` Ar Ao Aa

1.407885953
Population standard deviation

1.316956719

Arithmetic mean

53.375

Number of data

Sum of values

Sum of squares of values

22805.

} } inputs the same data twice (as above). You can also input multiple entries of the same data using -. To input the data 110 ten times, for example, press 110 -10 }. The above results can be obtained in any order, and not necessarily that shown above. To delete data you have just input, press A [.

kMaking Corrections During Data Input
Example 1: To change data you have just input. Correct 51 } } } Actual 50 } 31 Correction

A[ 51 } t}

Example 2: To change data you previously input. Correct 51 } } Actual 49 } } Correction 49 A [ 51 } 120 - 30 A [}

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 Memory Memory in.. A Y Memory minus.. A { Memory plus... | Memory recall.. Z fx-85B/fx-280 Memory Memory A recall. Memory B recall. Memory M recall.. Memory A store.. A J 1
Memory B store.. A J 2 Memory M store. A J 3
Special Display/memory swap.. A N, Ad Exponent.. e Internal rounding.. A b Parentheses.. O, P Pi (3.1415926536).. A x Select mode.. F Sexagesimal... I, A O Shifts key functions. A
Scientific Functions Arc cosine.. A V Arc sine.. A j Arc tangent.. A g Common antilogarithm. A Q Common logarithm.. R Convert to degrees.. A F 4 Convert to grads. A F 6 Convert to radians.. A F 5 Cosine... W
Cube... A N Cube root... A D Engineering.. A J, AP Factorial.. A f Fraction.. C Fraction.. A B Hyperbolic.. M Natural antilogarithm.. A U Natural logarithm.. T Percent.. A v Polar-to-rectangular.. A z Power.. w Random number.. A c Reciprocal.. A X Rectangular-to-polar.. A y Root.. A s Sine.. S Square.. K Square root.. A L Tangent.. h Permutation.. A m Combination.. A n
Statistics (SD Mode) Arithmetic mean. A ` Data delete.. A [ Data input... } Number of data.. A r Population standard deviation.. A p Sample standard deviation.. A q Statistical register clear.. A u 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.

NORM 1

With NORM 1, exponential notation is automatically used for integer values with more than 10 digits and decimal values with more than two decimal places.

NORM 2

With NORM 2, exponential notation is automatically used for integer values with more than 10 digits and decimal values with more than nine decimal places.
To switch between NORM 1 and NORM 2 Press F 9. 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. 1 \ 200 =

5. 03 0.005

NORM 1 format NORM 2 format
All of the examples in this manual show calculation results using the NORM 1 format.
kWhen you have a problem.
If calculation results are not what you expect or if an error occurs, perform the following steps. 1. F 0 (COMP mode) 2. F 4 (DEG mode) 3. F 9 (NORM mode) 4. Check the formula you are working with to confirm it is correct. 5. Enter the correct modes to perform the calculation and try again.

kMaking Corrections During Calculations
If you make a mistake when inputting a value (but did not yet press an operator key), use Q to backspace and delete input digits one-by-one. Or you can press k to clear the input entirely and start again.
In a series of calculations, press k while an intermediate result is displayed to clear only the last calculation performed. To change the operator key (+ , ,, -, \, w , As , 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.

kOverflow or Error Check

The following conditions make further calculation impossible. a. When a result (whether intermediate or final) or a t o t a l a c c u mu l a t e d i n m e m o r y i s g r e a t e r t h a n 9.999999999 1099. (E indicator appears on the display.) b. When function calculations are performed using a value that exceeds the input range. (E indicator appears on the display.) c. When an illogical operation (such as an attempt to calculate o and n while n 0) is performed during statistical calculations. (E indicator appears on the display.) d. When an illegal mathematical operation (such as division by zero) is performed. (E indicator appears on display.) e. The total number of nested parentheses levels exceeds six, or when more than 18 pairs of parentheses are used. ( 1 indicator appears on the display.) To clear any of the above conditions, press t and perform the calculation from the beginning. 26
In the case of condition e, you could also press k. This clears the intermediate result just prior to the overflow, so you can continue with the calculation from that point. No error occurs when the result is within the range of (11099)to (11099 ). Instead, the display shows all zeros.

kPower Supply

fx-82SOLAR/fx-260SOLAR This calculator is powered by a solar cell that converts available light into electrical power. Solar Cell Precautions The solar cell requires at least 50 lux of light to provide power. If available light is too low, the display may become dim, calculation functions may become impossible, or the contents of the independent memory may be lost. 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. The calculator retains memory contents no matter what the lighting conditions. The TWO-WAY POWER system uses two power sources: a solar cell and a single G13 Type (SR44 or LR44) battery. Weak battery power is indicated when memory contents spontaneously clear, or when the display darkens under poor light and cannot be restored by pressing 5. 27

Important!

Incorrect use of batteries can cause them to burst or leak, possibly damaging the calculator. Be sure to replace the battery at least once every three years, regardless of how much the calculator is used. Old batteries may leak, causing serious damage to the interior of the calculator. The battery that comes with the calculator when you purchase it is for testing only. It may not provide full service life. Low bettery power can cause memory contents to become corrupted or lost completely. Always keep written records of all important data. Always be sure to load the battery with its positive () side facing up (so you can see it). Never try to charge batteries, take them apart, or allow them to become shorted. Keep batteries away from direct flame and heat. Keep batteries out of the reach of small children. If swallowed, consult with your physician immediately. To replace the battery 1. Remove the screws that hold the back cover in place, and then remove the cover. 2. Remove the old battery. 3. Install a new battery, making sure that the positive () side is facing up (so you can see it). 4. Replace the back cover and secure it in place with the screws. 28

Screws

Battery
5. Press t to turn power on.
kOrder of Operations and Levels
Operations are performed in the following order of precedence. 1. Functions 2. xy, x 1/y, R P, P R, nPr, nCr 3. , 4. , Operations with the same precedence are performed from left to right, with operations enclosed in parentheses performed first. If parentheses are nested, the operations enclosed in the innermost set of parentheses are performed first. Registers L1 through L6 store operations. There are six registers, so calculations up to six levels can be stored. Each level can contain up to three open parentheses, so parentheses can be nested up to 18 times. Example: The following operation uses 4 levels and 5 nested parentheses. 2-O OO3 +4 -OO5 +4 The table on the next page shows register contents following the above input.
Register x L1 L2 L3 L4 L5 L6 4

(( ((( 3 2

kFormulas, 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, can be calculated within a range of 180 180. The calculation range is the same for radians and grads.

Y P (x, y) Pol y 0 x X

Y P (r, ) r Rec 0
Permutation Input range: n r 0 (n, r : integers) Formula: nPr Combination Input range: n r 0 (n, r : integers) Formula: nCr n! n!(nr)! n! (nr)!
Population Standard Deviation (xi x)

x2 (x)2 / n

Sample Standard Deviation n 1

(xi x)

Arithmetic Mean o

xi x n n

kSpecifications
Power Supply : fx-82SOLAR/fx-260SOLAR : Solar cell fx-85B/fx-280 : CASIO TWO-WAY POWER System: solar cell plus one G13 Type (SR44 or LR44) battery Battery Life (fx-85B/fx-280) : Approximately 3 years (1 hour use per day) on LR44/SR44 battery Input Ranges : Functions sinx cosx tanx sin1x cos1x tan 1x sinhx coshx tanhx sinh x
Input Range However, for tan x: (DEG) x9109 x 90(2n1):DEG 7 (RAD) x510 rad x 2(2n1):RAD 10 (GRA) x110 grad x 100(2n1):GRA x 1 x x 230.2585092 x x 1 x 32 For sinh and tanh,errors are cumulative and accuracy is affected at a certain point when x=0.

cosh1x

Functions tanh 1x logx/lnx 10 e x
Input Range x 1099 x x 10100 x 230.x x x 2.x ; x 0 x 0 x 69 (x is an integer) 0rn n 11010 (n and r are integers) x2 y 0 r 110100 (DEG) 9109 (RAD) 5107 rad (GRA) 11010 grad However, for tan: 90(2n1):DEG 2(2n1):RAD 100(2n1):GRA

x3 1/x

nPr/nCr RP
Input and Results Total of hour, minutes, and seconds digits must be 10 or fewer (including separator symbols). Decimal Sexagesimal Conversions x 2777777.

Functions

Input Range x 0: 110100 y log x 100 x 0: y 0 x 0: y n; 1 (n is an integer) 2n1 However: 110100 y log x100 x 0:y 0 1101001/y log x 100 x 0: y 0 x 0: y 2n1; 1 (n 0; n is an integer) n However: 1/y log x100 Total of integer, numerator, and denominator must be 10 digits or less(including division marks). x 11050 n 110100 n , o : n 0 n 1 : n 0, 1

a b/ c

Errors are cumulative with such internal continuous calculations as xy, x1/y , x!, and 3 x, so accuracy may be adversely affected.
Operating Temperature: 0C40C (32F104F) 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 exponent up to 1099

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