fx-115ES PLUS
fx-991ES PLUS C
(2nd edition / NATURAL-V.P.A.M.)
Before Using the Calculator
Calculation Modes and Calculator Setup
Inputting Expressions and Values
- ▶Basic Input Rules
- ▶Inputting with Natural Display
- ▶√ Form Calculation Range
- ▶Using Values and Expressions as Arguments (Natural Display only)
- ▶Overwrite Input Mode (Linear Display only)
- ▶Correcting and Clearing an Expression
Basic Calculations
- ▶Toggling Calculation Results
- ▶Fraction Calculations
- ▶Percent Calculations
- ▶Degree, Minute, Second (Sexagesimal) Calculations
- ▶Multi-Statements
- ▶Using Engineering Notation
- ▶Remainder Calculations
- ▶Recurring Decimal Calculations
- ▶Prime Factorization
- ▶Calculation History and Replay
- ▶Using Memory Functions
Function Calculations
- ▶Pi (π), Natural Logarithm Base e
- ▶Trigonometric Functions
- ▶Hyperbolic Functions
- ▶Angle Unit Conversion
- ▶Exponential Functions
- ▶Logarithmic Functions
- ▶Power Functions and Power Root Functions
- ▶Integration Calculations
- ▶Differential Calculations
- ▶Σ Calculations
- ▶Π Calculations
- ▶Rectangular-Polar Coordinate Conversion
- ▶Factorial Function (!)
- ▶Absolute Value Function (Abs)
- ▶Random Number (Ran#)
- ▶Random Integer (RanInt#)
- ▶Permutation (nPr) and Combination (nCr)
- ▶Rounding Function (Rnd)
- ▶Greatest Common Divisor (GCD) and Least Common Multiple (LCM)
- ▶Integer Part of a Value (Int) and Largest Integer that does not Exceed a Value (Intg)
- ▶Using CALC
- ▶Using SOLVE
- ▶Scientific Constants
- ▶Metric Conversion
Using Calculation Modes
- ▶Complex Number Calculations (CMPLX)
- ▶Statistical Calculations (STAT)
- ▶Base-n Calculations (BASE-N)
- ▶Equation Calculations (EQN)
- ▶Matrix Calculations (MATRIX)
- ▶Creating a Numerical Table from Two Functions (TABLE)
- ▶Vector Calculations (VECTOR)
- ▶Inequality Calculations (INEQ)
- ▶Using VERIFY (VERIF)
- ▶Distribution Calculations (DIST)
Technical Information
- ▶Errors
- ▶Before Assuming Malfunction of the Calculator...
- ▶Replacing the Battery
- ▶Calculation Priority Sequence
- ▶Calculation Ranges, Number of Digits, and Precision
- ▶Specifications
- ▶Verifying the Authenticity of Your Calculator
Frequently Asked Questions
Replacing the Battery
The battery needs to be replaced after a specific number of years. Also, replace the battery immediately after display figures become dim.
A low battery is indicated by a dim display, even if contrast is adjusted, or by failure of figures to appear on the display immediately after you turn on the calculator. If this happens, replace the battery with a new one.
Important!
Removing the battery will cause all of the calculator’s memory contents to be deleted.
1. Press (OFF) to turn off the calculator.
2. On the back of the calculator, remove the screws and the cover.
3. Remove the battery, and then load a new battery with its plus (+) and minus (-) ends facing correctly.
4. Replace the cover.
5. Initialize the calculator: (CLR)(All)(Yes).
Do not skip the above step!