# Exam Calculator There are a small number of questions on the exams which require a calculator. You may not bring a calculator to the exam, but an electronic calculator is included in the exams. The examination calculator (TI-30XS) is a bit unusual, so make sure you read this page in preparation for the exams.

#### Buttons The buttons in the figure above will be useful for the exam.

• <2nd> selects the function shown in yellow above the main buttons
• <ex> (click <2nd> <ln> buttons) is the exponential function
• <√> (click <2nd> <x2> buttons) is the square root function
• <-> is subtraction
• <(-)> is change the sign from positive, +, to negative, –
• <ans> (click <2nd> <(-)> buttons) uses the result of the previous calculation
• <enter> calculates the result

Button names, like <2nd>, are enclosed in angle brackets, <…>, for clarity.

#### Click the Function Button First

For urinary functions (functions like ex, which take only one number) the function is entered first.  Clicking on buttons <2nd> <ln> on the keyboard results in: #### Change Sign versus Subtraction

The calculator has different buttons for change sign and for subtractions:

• <(-)> changes the sign plus-to-minus or minus-to-plus (+/-)
• <-> preforms subtraction, e.g. 9 – 5

After entering the <ex> function by clicking <2nd> <ln>, clicking the following buttons calculates e-.693•12/6 (result shown in the figure at the beginning):

<(-)> . 6 9 3 x 1 2 ÷ 6 <enter>

#### Parentheses

Parentheses can be used to group calculations.  Pushing the following buttons

<2nd> <√> ( 4 x 9 ) – <2nd> <√> ( 3 x 3 ) <enter>

results in: #### Previous Result

The previous result can be inserted into the current calculation using <ans> which is entered as <2nd> <(-)>.  After the previous example, clicking the following buttons

<2nd> <√> ( 4 x 1 6 ) ÷ <2nd> <(-)> <enter>

results in: It may just be simpler for some people to write down intermediate results and reenter them later.

#### Power Function ^

The power function, Xy, is entered using the button labeled, ^. <^> is not circled in the buttons figure; it is the orange button above <x2>.  Clicking the following buttons

3 <^> 5 <enter>

results in: 