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Using Entry and Ans

by derek

Entry and Ans are two of the most incredibly useful functions of the home screen for the calculator. They will save you much time in repeat functions or if you're performing several operations on one continuing piece if data.

Ans

Ans is one of those handy dandy system variables. It's called a systems variable because it is stored by the operating system, although you can store to it indirectly. It stores the answer to the last command given to it. Say you type in: 5+6 and hit enter. It would display 11 and that would be stored in Ans. If you wanted to divided this new number by 2, all you would have to do is hit / and 2. When starting a new command (entry) by pressing one of those operation keys (+-*/) it automatically uses Ans but you can put Ans anywhere in the expression.It's right above the (-) key

(7*2)/Ans

Since we already stored 11 into Ans the above expression will result in 1.272727273 or simply 14/11.

You can also split larger expressions to make them easier to type and understand. (5+3)/2+8*4 would become:

5+3 [ENTER]            8
Ans/2 [ENTER]          4
Ans+8*4 [ENTER]   36

Of course you have to remember the order of operations (),^,*/,+- but it saves possible human error of leaving out a parenthesis, which is the most common human error on entries.

Entries

Your most recent commands are stored with the Entry system variable. It usually stores up to 10 entries but that varies due size (it can only store up to 128 bytes). You can cycle through your entries by pressing 2nd [Enter]. It goes from most recent to least. After the least recent, it starts at the most all over again. It will display the entry on the screen to be run or modified.

Using Entry can save a lot of typing for repeated actions. Say you're running the same equation but with different numbers. Take the quadratic equation:

-b +- radical(b^2 - 4ac) all over 2a.
you can't put (+-) in the calculator so you would put: (-b + rad(b^2 - 4ac))/(2a), run it, and then hit 2nd [Enter] and change the first + to a -. You also could run this equation numerous times with different numbers by hitting 2nd [Entry] and changing the appropriate numbers.

You can delete all of your entries as described on the Memory Management page.

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