Sharp EL9900C EL-9900C - Page 43

Chapter 3: Basic Calculations - Basic Keyboard 2. Arithmetic Keys Performing addition, subtraction, multiplication and division 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 A Note about expressions An expression is a mathematical statement that may use numbers 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 33