Notes on using the Calculator

1. To use the calculator,
• click in the entry box
• enter an expression
• press return or click on the button "Compute"
• the result will appear in the box below

Examples:

• 4 * Pi * 6400^2 (computes the earth's surface area in square kilometers)
• 4 * Pi * (6.4e6)^2 (computes the earth's surface area in square meters)
• e^{ (-1.5) / 2}

2. You may use the following binary operators:
- for subtraction
* for multiplication
/ for division
^ for exponentiation
A common mistake is to forget * when multiplication is intended.

3. The special mathematical constants, pi = 3.14... and e= 2.78... are known and may be referenced by PI and E (case is not important).

4. Numbers may be entered in scientific notation: the syntax is, for example,
• 1e-12 which denotes 10^(-12) (it is important to have a "1" preceeding the exponent).
• 5.9e24 which denotes 5.9*10^(24).

5. The usual rules of precedence apply when binary operations are concatenated. For instance, exponentiation is performed first, followed by multiplication and division and finally addition and subtraction. If in doubt, use parentheses to indicate the order in which operations should be performed: ( ), { } and [ ].

6. Case is insignificant; that is, TaN(1) is the same as tan(1).

7. Blanks are ignored; that is t A n (1 ) is the same as tan(1).

8. The following mathematical functions are supported. While it is not necessary to delimit the argument to such a function, it is highly recommended. This insures that you produce the value you expect. For instance, you should write tan(Pi^2) or tan(Pi)^2 rather than tan Pi^2. (For your information, tan Pi^2 produces tan(Pi)^2.)

• Abs: Absolute value
• Acos or Arccos: Inverse cosine
• Asin or Arcsin: Inverse sine
• Atan or Arctan: Inverse tangent
• Ceil: returns the smallest integer larger than or equal to the argument
• Cos: Cosine
• Cot: Cotangent
• Csc: Cosecant
• Delta: Delta function
• Floor: returns the greater integer smaller than or equal to the argument
• Ln: Natural logarithm
• Sec: Secant
• Sgn: returns -1 if the argument is negative, 0 if 0 and 1 if positive
• Sin: Sine
• Sqrt: Square root (sqrt(4) is equivalent to 4^(1/2))
• Tan: Tangent