A companion video to this tutorial is available at the bottom of the page.  The TNS file for this tutorial is currently unavailable.

Introduction to using the calculator application:
The most important thing to know when using the calculator application is how to access it. To add a calculator application to a document, press the home button (the one with the house icon), then press 1 to select the calculator. You can now use the calculator application. You can add as many calculator apps to a document as you want, so if you need another just press home+1. The calculator app can store a total of 99 previous results. Once you have reached that limit, it will start erasing the oldest results. You can use the navpad (big circle with arrows on it) to scroll up and down to see previous results. If you need to use a previous result in your current computation, you can highlight the previous result, press ctrl+c, then scroll back down to your current computation, and press ctrl+v. If you want to clear a previous result, highlight it and press the backspace button (the one with an arrow facing the left). If you would like to clear all previous results, press menu+1+5. If you need to undo an action, such as deleting a result, press ctrl+esc or ctrl+z. You are now ready to begin learning how to use the calculator application.

Basics:
Basic computations are entered the same way that they are written on paper. For example, to multiply 3 and 4, just hit 3, then x, then 4, then press enter to have the computation be performed. Remember that the calculator performs computations in the order of operations, so use parenthesis accordingly. If you have a value that you will be using often, or would just like to have it saved, you can use a variable. A variable stores a number so that you can use it in later computations. You can name a variable whatever you want, and to use it again later, you can type in its name, and the text will be replaced by the value stored in the variable. You can see a list of all the variables that you have created by pressing the var key and using the navpad to select the variable that you would like to use. Creating a variable is very simple. First, type what you want the variable to be named. Next, type := after the name. Finally, type the value that you wish to store in the variable. If you would like to change the value of a variable, you can follow the same syntax that you use to create a variable, except you replace the value part of the syntax with the new value to store in the variable.

Fractions:
One great improvement that the TI-Nspire has over the TI-84 is that it can handle fractions symbolically. What I mean by that is on the TI-84, if you typed in a fraction and pressed enter, it would give you the decimal approximation. However, on the TI-Nspire, as long as there are no decimals in your calculation, the answer will remain in fraction form. For example, if you entered 1/4+1/2 on the TI-84, you would get .75 as your answer. However, entering the same calculation on the TI-Nspire will give you the answer 3/4. If you need the decimal approximation of a fraction, just type in the fraction, and instead of pressing enter, press ctrl+enter. This also works if you want the decimal approximation of the previously entered calculation. If you have a decimal that you want to turn into a fraction, there is a built in function to do that. First, type in the fraction or make sure that the last result on the calculator app is the decimal, then press menu+2+2+enter. You will end up with the fraction form of the decimal. If you try this with the decimal form of irrational fractions, such as 1/3 or 1/7, you may end up with an incorrect result. The reason for this is because of how the TI-Nspire makes the fractions. As you may have already noticed, when you use the function to make a fraction, it looks like this: Ans?approxFraction(5.E−14). The 5.E-14 tells the calculator how precise the fraction needs to be. The default value is very precise, and will likely give you an incorrect answer for irrational decimals. To fix this problem, move your cursor inside the parenthesis, and press the backspace button until the 5.E-14 is erased. Then, you can enter in a value that is less precise, such as 0.000001 or 0.0001. The fewer zeroes that you have, the less decimals that the TI-Nspire will check. A lot of the time, leaving the default value of 5.E-14 will work just fine, but if it seems to be giving incorrect results, try using a less precise value. After you press enter, the value that you entered, such as .0001 will change to look something like this: 1.E-4. This is normal, so don't be confused by it. To see examples of everything taught on this page, go to the next page.

Expressions:
If you want to test a condition with 2 expressions, you enter it into the calculator the same way that you would write it on paper. For example, it you wanted to know if the fraction 6/23 is greater than 8/25, you would insert a fraction template(ctrl+÷), fill in the numerator and denominator (6 and 23), press the greater than key (>), then insert a second fraction template and fill in the numerator and denominator (8 and 25). If this statement is true, then the result will say true, otherwise it will say false if it is false. This also works if you want to use variables. For example, lets say that x=3 and y=4. If you wanted to see if 4x+7 was equal to 5y-1, you would enter it into the calculator like this:
x:=3
y:=4
4x+7=5y-1
If you are not using the CAS version of the TI-Nspire, it is important to remember to always define variables that you will be using before you use them, like in the example above. Otherwise, it may return an error. All of the keys for testing expressions are the little gray keys going along the left side of the calculator. The equals, greater than, and less than signs all have their own keys, however the not equals to, greater than or equal to, and less than or equal to don't have their own keys. To access those symbols, just press control before pressing the corresponding key. For example, to insert the ≠ symbol, press ctrl+=. To insert the ≤ symbol, press ctrl+<. Finally, to insert the ≥ symbol, press ctrl+>. I have included numerous examples on the next page to demonstrate what you have just read, as it was a lot of information and may be confusing.

Useful Functions
Now that you have learned how to perform normal computations on the calculator app, it is time to learn about some more advanced functions available to use. The first function that will be explained is nSolve().
nSolve()
You can use nSolve() to solve a single variable equation. It is very easy to use. Here is the syntax for using it:
nSolve(equation,variable)
The equation is what equation needs to be solved. Make sure that there is an equal sign somewhere in the equation, and that you don't just put an expression. The variable part of the syntax is the variable that you want to solve for. In most cases, this will be x, but if your equation uses a different variable, such as z, you can just put z in it's place. If you have an equation in 2 variables that you would like to solve, you can use nSolve() to do it as long as you know the value of one variable. For example, lets say that you want to solve the equation 3a+4b=10, and you already know that the value of b is 1. You can use the | key to specify that you already know the value of b. Here is how that example would look: nSolve(3a+4b=10,a)|b=1. nSolve() will give all of the correct solutions for linear equations, but will only give one answer for equations with a degree higher than 1. What that means is that if you have anything above x^1 in your equation, like x^2, x^3, ect., then you won't get all of the answers.
factor()
factor() is another very useful function, especially if you are using it on the TI-Nspire CAS instead of the normal TI-Nspire. The syntax for factor() is the following:
factor(number)
What factor does it take whatever number you give it and give you the prime factorization. If you don't know what that is, here is a simple explanation. A prime factorization is finding a group of prime numbers that will multiply to equal the specified number. For example, the prime factorization of 100 is 2^2*5^2.
nDeriv()
We will now get into calculus functions, so if you aren't to calculus yet, you can ignore these last 2 functions. nDeriv() is used to find the derivative of an expression. Here is its syntax:
nDeriv(expression,variable)
The expression is the expression that you want to take the derivative of, and the variable is the variable used in the expression. For example, if you wanted to find the derivative of x^2, you would enter it like this: nDeriv(x^2,x). The result would be 2*x, which is the derivative of x^2. You can then plug in a value for x to find the derivative at a specific point. For example, with the previous example, to find the derivative at x=4, you would plug 4 into the answer: 2*x=2*4=8. So at x=4, the derivative of x^2 is 8. If you just want a derivative at a specific point, you can use a method similar to using 2 variables with nSolve(). You can use the | key to specify a specific point. For example, to simplify the previous example, you would write it like this: nDeriv(x^2,x)|x=4. This is a very powerful function to use, and will be very useful for checking your work in calculus.
nInt()
The last numeric function that will be explained in this section is nInt(). It is used to find the integral of an expression between 2 points. However, it cannot compute the indefinite integral for an expression. Here is it's syntax:
nInt(expression,variable,low,high)
The expression and variable portions of the syntax should be self explanitory by now, because it has been used in many other functions. The low is the first x value, and the high is the second x value. For example, if you wanted to find the integral of x^2 between x=2 and x=4, here is how you would write it: nInt(x^2,x,2,4). The result from that would be 18.6667, and if you use the approxFraction() function, you would see that it is 18+2/3, which is the same as 56/3.

Conclusion
By now, you should be able to do anything that you need to do on the TI-Nspire calculator app. However, I'm going to leave you with some hints to help you with discovering more useful functions.
*If you need to find the syntax of a function, you can find it in the catalog. To access the catalog, press the button with the open book on it. You can scroll down to find a function, or press the first letter of the function to jump to that section. The catalog is a great place to discover and learn about new functions
*If you are confused about anything and need some help, you can post your question on the forums at lafacroft.com. You can also post your question at the TI-Nspire Google Group. To get to the google group, just go to lafacroft.com, and you will see the link to it on the right side of the page