Sharp EL-9900 Calculator User Manual


 
33
Chapter 3: Basic Calculations — Basic Keyboard
2. Arithmetic Keys
There are various keys for arithmetic calculations. Use the +
- | =, _, ( and ) keys to perform
basic arithmetic calculations. Press E to solve an equation.
E Executes an expression.
Example
Calculate 1
+ 2.
# C 1 + 2 E
An expression is a mathematical statement that may use num-
bers and/or variables that represent numbers. This works just like
a regular word sentence; one may ask “how are you?”, and you
may answer “okay.” But what if an incomplete sentence is thrown,
such as “how are”? You’ll wonder, “how are... what?”; it just
doesn’t make sense. A math expression needs to be complete as
well. 1 + 2, 4x, 2sinx + cosx form valid expressions, while “1
+and
“cos” do not. If an expression is not complete, the calculator will
display an error message upon pressing the E key.
+ Enters a “+sign for addition.
Example
Calculate 12 + 34.
# C 1 2 + 3 4
E
- Enters a “sign for subtraction.
Example
Subtract 21 from 43.
4 3 - 2 1 E
Performing
addition,
subtraction,
multiplication
and division
A Note about
expressions