User manual CASIO FX-250HC

[. . . ] Wipe it with a soft cloth, or with a cloth that has been dipped in a solution of water and a neutral detergent and wring out. · In no event will the manufacturer and its suppliers be liable to you or any other person for any damages, expenses, lost profits, lost savings, or any other damages arising out of malfunction, repairs, or battery replacement. The user should prepare physical records of data to protect against such data loss. · Never dispose of batteries, the liquid crystal panel, or other components by burning them. [. . . ] . 08125 J 81. 25­03 · Example 6: To generate a random number between 0. 000 and 0. 999. Example (results differ each time) Ac 0. 664 kCoordinate Conversion · Example 1: To convert polar coordinates (r 2, rectangular coordinates (x, y). (DEG mode) x y 2 A z 60 = 60°) to DEG 1. DEG A N 1. 732050808 ANswaps displayed value with value in memory. · Example 2: To convert rectangular coordinates (1, 3 ) to polar coordinates (r, ). (RAD mode) r 1Ay3L= RAD 2. RAD A N 1. 047197551 kPermutation · Example: To determine how many different 4-digit values can be produced using the numbers 1 through 7. 7Am4= -- 15 -- 840. kCombination · Example: To determine how many different 4-member groups can be organized in a group of 10 individuals. 10 A n 4 = 210. Statisticasl Calculations (SD Mode) · Press Flto enter the SD Mode for statistical calculations using standard deviation. · Example: To calculate n 1, n, o, n, x, and following data : 55, 54, 51, 55, 53, 53, 54, 52. Enter SD Mode. Input Data. x2 for the Fl A u 55 } 54 } 51 } 55 } 53 } } 54 } 52 } 0. SD SD 52. SD Sample standard deviation Aq Ap -- 16 -- 1. 407885953 SD Population standard deviation 1. 316956719 Arithmetic mean A` Ar Ao Aa SD 53. 375 SD Number of data 8. SD Sum of values 427. SD Sum of squares of values 22805. · }} inputs the same data twice (as above). · You can also input multiple entries of the same data using -. · The above results can be obtained in any order, and not necessarily that shown above. · To delete data you have just input, press A[. -- 17 -- kMaking Corrections During Data Input · Example 1: To change data you have just input. Correct 51 } 130 31 } 130 31 } Actual 50 } 120 120 31 Correction A[ 51 } t130 31 } t130 31 } · Example 2: To change data you previously input. Correct 51 } 130 31 } Actual 49 } 120 30 } Correction 49 A [ 51 } 120 - 30 A [130 31 } Technical Information kKey and Their Functions · General Arithmetic calculations . . . . . . . . . . . . . . . . . . . . . . . . . . 0 ­ 9, l Power off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E · Memory Memory in . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A -- 19 -- · Scientific Functions Arc cosine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . There is no indication on the display of which format is currently in effect, but you can determine the setting by performing the following calculation. ­03 0. 005 NORM 1 format NORM 2 format · All of the examples in this manual show calculation results using the NORM 1 format. kWhen you have a problem. . . If calculation results are not what you expect or if an error occurs, perform the following steps. -- 22 -- kMaking Corrections During Calculations · If you make a mistake when inputting a value (but did not yet press an arithmetic operator key), press k to clear the value and then input the correct one. · In a series of calculations, press k while an intermediate result is displayed to clear only the last calculation performed. · To change the operator key (+, , , -, \, A w, A s, etc. ) you just pressed, simply press the correct operator key. [. . . ] There are six registers, so calculations up to six levels can be stored. · Each level can contain up to three open parentheses, so parentheses can be nested up to 18 times. · Example: The following operation uses 4 levels and 5 nested parentheses. 2-OOO 3+ 4-O O5 +4 The table below shows register contents following the above input. -- 26 -- Register x L1 L2 L3 L4 L5 L6 4 Contents (( 5 4 ((( 3 2 kFormulas, Ranges, and Conventions The following are the formulas, ranges, and conventions that are applied to various calculations that can be performed using this calculator. Coordinate Transformation · With polar coordinates, can be calculated within a range of ­180° 180°. [. . . ]