The TI.25X Solar Calculator The TI-25X Solar calculator offers you a wide range of mathematical and statistical capabilities. This manual explains these capabilities. Basic Operations To turn the calculator on, expose the solar panel to adequate light and press + ([ON]). Key + ([ON]) - ` Function If the calculator is off, turns the unit on, clears the display, and resets angle units to degrees.
The Display You can enter a maximum of eight digits in the display. Any digit key pressed after the eighth is ignored. Indicator – 2nd D R G () STAT K M E Meaning The displayed number is negative. The ` key has been pressed to access the second function (written above the key) of the next key pressed. Angle units are set to degrees. Angle units are set to radians. Angle units are set to grads. One or more parentheses are open. The calculator is in statistics mode.
Scientific Notation In scientific notation, a number is expressed as a mantissa multiplied by 10 raised to a power (exponent). mantissa exponent floating mantissa sign Key a `\ exponent sign Function Example: To enter 1.2345 × 10 6: 1.2345 a 6 1.2345 06 Removes a displayed result from scientific notation and displays it in standard decimal format. Entering a Number in Scientific Notation 1. Enter the mantissa. If it is negative, press @. 2. Press a. Two zeros appear on the right side of the display.
Correcting Entry Errors At any point in a calculation, you can press - twice to clear all calculations, including any errors, and start over. Clearing an Error Condition The display shows E when an error, overflow, or underflow occurs or when you enter an improper operation. No entry from the keyboard is accepted until you press -, which clears the error condition and all pending operations.
Basic Functions Key p, o, n, m Function Perform addition, subtraction, multiplication, and division. Example: 12 n 5 p 60 l 120. l Completes all pending operations. Example: 4 n 5 p 9 l 29. @ Changes the sign (positive or negative) of the displayed number. Example: 8 @ p 12 l 4. ij Operations enclosed in parentheses are given priority over operations outside the parentheses. You can enter up to 15 levels of parentheses. l closes any open parenthetical expressions. Example: 12 n i 5 p 6 l 132.
Key V `m G Z `l b `k c `j Function Calculates the square of the displayed number. Calculates the square root of the displayed number. Calculates the reciprocal (x−1) of the displayed number. Raises the displayed number (y) to a specified power (x). Calculates a specified root (x) of the displayed number (y). Calculates the common logarithm (base 10) of the displayed number. Calculates the common antilogarithm of the displayed number (10 raised to the power of the number).
Using the Memory The calculator’s memory can store data as long as the calculator is on. You can store a number in memory for repeated use in a calculation or to keep a running total. Key r s t u Function Stores the displayed number in memory, replacing any previously stored number. To clear the memory, press r when zero is displayed. Example: 23 r p 2 l M 25. Recalls and displays the number stored in memory. Does not change or clear the number in memory. Example: s p 3 l M 26.
Constant Calculations The constant key h simplifies repetitive calculations by storing a number and its associated operation for repeated use. To enter a constant operation: 1. Key in the repetitive number (m). 2. Press the operation key you want. 3. Press h. Key mph moh mnh mmh mZh Function Adds m to each subsequent entry. Subtracts m from each subsequent entry. Multiplies each subsequent entry by m. Divides each subsequent entry by m. Raises each subsequent entry to the mth power.
Angle-Unit Setting Before starting a trigonometric calculation, use the K key to select the appropriate angle-unit setting (D—Degree, R—Radian, or G—Grad). Key K `x Function Changes the angle-unit setting without affecting the displayed angle value. Changes the angle-unit setting and converts the displayed angle value to its equivalent for the new setting. Example: Convert 45°. (If necessary, press K until D is displayed.) 45 D 45. `x R 0.7853982 `x G 50. `x D 45.
Degree Format Conversions An angle measured in degrees, minutes, and seconds (DMS) must be converted to decimal degrees (DD) before you can use it in a calculation. Degrees, Minutes, and Seconds DMS angles are entered in D.MMSSsss format. D . MM SS sss Degrees (°)—0 to 8 digits Decimal point separator Minutes (')—must be 2 digits Seconds (")—must be 2 digits Fractional part of a second For example, enter 48°5'3.5" as 48.05035. Decimal Degrees DD angles are entered in D.ddddddd format. D .
Converting Angle-Measurement Format The TI-25X Solar can easily convert an angle measurement from one degree format to the other. Key ` [DMS8DD] ` [DD8DMS] Function Converts the displayed value from degrees, minutes, and seconds (DMS) to decimal degrees (DD). Enter the angle in D.MMSSsss format. If necessary, include leading zeros as needed to place the digits in the proper positions. Then press ` [DMS8DD]. Converts the displayed value from decimal degrees (DD) to degrees, minutes, and seconds (DMS).
Rectangular-to-Polar Conversions Pressing ` [R8P] converts rectangular coordinates (x,y) to polar coordinates (r,Θ). Example: Convert the rectangular coordinates (10, 8) to polar coordinates. Comments Enter x and y Value of Θ Value of r Value of Θ Keystrokes 10 ` 8 ` [R8P] ` ` Display 8. 38.659808 12.806248 38.659808 To alternate between the two converted values (r and Θ), press ` repeatedly.
Statistics Functions The TI-25X Solar can perform statistical analysis on onevariable data. Key g Function Enters the displayed number into the statistics register as a data point. `z Removes the displayed number from the statistics register. ` Calculates the mean of the entered data. `ƒ Calculates the population standard deviation of the entered data (n weighting). `‚ Calculates the sample standard deviation of the entered data (n . 1 weighting).
Example: Analyze the following test scores. Assume that the four students are the entire population: 96, 81, 87, 70. Comments Clear display Clear register 1st entry 2nd entry 3rd entry (incorrect) 3rd entry (removed) 3rd entry (correct) 4th entry Mean (class average) Standard Deviation Variance Keystrokes ` [CSR] 96 g 81 g 97 g 97 ` z 87 g 70 g ` `ƒ V Display 0. 0. 1. 2. 3. 2. 3. 4. 83.5 9.4472218 89.
Error Conditions The display shows E when an error occurs or when you attempt certain operations. Press - to clear an error condition. In Case of Difficulty 1. If the digits fail to appear on the display: ¦ Check to be sure that no part of the solar panel is covered. ¦ Check the intensity of the light source. The light may be too dim to operate the calculator. 2. Press + and try the calculation again. Review the operating instructions to be certain the calculations were performed properly. 3.
TI Product and Services Information For more information about TI products and services, contact TI by e-mail or visit the TI calculator home page on the world-wide web. e-mail address: ti-cares@ti.com internet address: http://www.ti.com/calc Service and Warranty Information For information about the length and terms of the warranty or about product service, refer to the warranty statement enclosed with this product or contact your local Texas Instruments retailer/ distributor. 16.