How do I n(cube) a number? How do I use the calculator to compute the following number: 421.875 = n(cubed) (421.875) superscript 1/3? the answer given is n = 7.5 I cannot get that answer...

There are several ways to find the cube root of a number on a calculator. On this calculator, we can use the nth root button, by using the yellow shift button with the ^ key. Another way to do this is just to use the ^ key.

For example, the cube root of 8 is performed by the following key sequence: 8, shift, ^, 3.

Another sequence is: 8 ^ (1/3)

Good luck.

Paul

For cube roots, use the cube-root function in the MATH menu. For example, to calculate the cube root of 8, press MATH 4 8 =

For other roots (including cube root), use the xth-root function in the MATH menu. For example, to calculate the fifth root of 32, press 5 MATH 4 3 2 =

. 9 3 3 x^ 1 . 5

x^ is marked on the keyboard as an x with a superscript rectangle on the key above the sin key. This function lets you raise a value to any number, including 2 and 3.

Here is another more detailed way to solve this problem, using dimensional analysis:

You want to convert cm3 to m3.

• Consider the two different units without their superscripts: that is, cm and m.
• Relate them to each other: that is, 1 m = 100 cm is probably the easiest way.
• Use the above equivalency by rewriting it as a ratio: 1 m/100 cm or 100 m/1 cm.
• Now cube each one of the above ratios: that is, 1 m^3/(100 cm)^3 or (100 cm)^3/1 cm^3. You want to do this cubing, because, you want to match the unit in the given starting quantity, 1 cm^3.
• Next multiply one of the above ratios (also called the "conversion factor") times the given quantity, as followed below:

x-th root of a number equals the number to the power of (1/x) where x is a natural number.

square root = to the power of (1/2)
cubic root = to the power of (1/3)

http://answers.yahoo.com/question/index?qid=20071129202945AAOndt7

You can multiply a number by 1/3rd to get the cube root or

Under the MATH button, the fourth option down will give you cube root. Any n root beyond that will require the x^(1/n) method.

You can enter any root by typing the number, then hitting MATH and 5, which brings up the root symbol with the x in front of it: x√. So the fifth-root would be 5 -> MATH -> 5 and then whatever number you want to get the fifth-root for: 5x√10 for example. As someone else had mentioned, you can also raise it to a rational power: 3^(1/3) which would be the same as the cubed root of 3, but you could also type: 3 -> MATH -> 5 -> 3 and get the same answer, but looking like this in your calculator: 3x√3. The option for 4 actually is a predefined cubed-root, and the one for option 5 there is the root symbol that can be used with any number before it to get any root you want. There are no parenthesis as you get when using the predefined square-root and cubed-root functions, though, so you may want to type them in yourself if entering a long string of operations in the calculator at one time to make sure the calculator doesn't include numbers under the root that you don't want it to. But I guess it depends on preference in terms of what method you choose between the rational exponents or the root symbol (and most would go with whichever seems easiest and quickest to enter), but you asked specifically how to get the cubed-root on the TI-83 Plus, so there's my best attempt at answering your question.

You are asking how to enter (3)(cube of 2x)-1, or (3)(cube of (2x-1), with x = -13?

For first:

13
=/- (below 3 key)
X
2
=
2nd
x cubed (above 1 key)
X
3
-
1
=
Answer -52,729

For second:

13
=/- (below 3 key)
X
2
-
1
=
2nd
x cubed (above 1 key)
X
3
=
Answer -59,049

You use the y^x (y to the x) key along with the 2nd function key. That does the opposite operation.

So, let's pick something we know the answer to as an example. How about the cube root of 8? We know 8 = 2 X 2 X 2, so the cube root of 8 will be 2.

Here's how:

8 2nd y^x 3 =

The display will show 2.

The three is the root you want. You can put in any number, with 2 being the square root, 3 the cube root, etc.

There is a way to do it. I believe you go into "complex" or "math" buttons. These buttons are yellow on the calculator. Therefore, to access them you must hit "2nd" then the button.

Better yet, you can also get around this dilemma another way. You can enter "the cubed root of x" by raising x to 1/3.

For example the cubed root of x = x^(1/3). It is best to place parentheses around 1/3 so the calculator knows exactly what you mean.

Another example, the "cubed root of (x + 1)" can be entered by:
(x+1)^(1/3) Note the parenteses around both (x+1) and (1/3). This applies if the radical cover both "x" and "1".

Hope this helps.