Casio fx 115 ES - Square and Nth Roots

[CharlieBoysMommy]

index 3 sqrt 9 (times) index 3 sqrt 6 = ?

[CharlieBoysMommy]

I was not sucessful with the radical mulitiplication problem I posted, can you help, again? ty

[rstallworth12]

Hello @CharlieBoysMommy, as I stated below, the Casio does not perform operations on variable terms (such as adding, subtracting, multiply or dividing terms that contain variables). Here is how you can tell when you can use the Casio. If the original problem has an equal sign with terms on (each side) of the equal sign, you can use the Casio. If it's just an operation between two or more terms (as what you have above) you cannot.

[CharlieBoysMommy]

Thanks! Yes, it works - I got X=9, also. I am now going to attempt this multiplication problem using some of these steps: index 3 sqrt 9 x index 3 sqrt 6=

[CharlieBoysMommy]

I am looking to see if you have a video that explains solving or adding and multiplying radicals together when they have a variable under the square root sign. Is their a video for this on YouTube? I love your videos! thanks :)

[rstallworth12]

Hello @CharlieBoysMommy , to my knowledge, the Casio does not perform operations on (variable) radical terms. However, it will solve radical equations. For example, if you are trying to solve the equations sqrt(3x - 2) = 5, you could use the Casio to solve it. It will be difficult for me to type out the steps, but I'll try. I will have to use multiple windows to type it all in. I hope you will be able to follow. :-)

[rstallworth12]

1) Hit the square root key

2) Enter the expression 3X - 2 (you can access the variable "X" by selecting the "ALPHA" button then the " ) " button).

3) Move the cursor from under the radical sign, by hitting the right arrow on the circular navigation wheel.

4) Now select the (red) equal sign by selecting "ALPHA" then "CALC", then enter "5"

5) To solve it, hit "SHIFT", then "CALC"

[rstallworth12]

6) You should see "Solve for X" in the window, hit the "=" sign at the bottom right corner of calculator.

7) You should see, X = 9 on the second line of the screen.

Let me know if the steps don't work out.

[rstallworth12]

Note of Caution: Some of the more complicated radical equations can have more that one solution. To my knowledge, the Casio only generates one of them.

[894973bee]

can you show how to do trig

[rstallworth12]

@894973bee, I don't have any immediate plans to do trig videos. However, if you have a specific question about to enter a particular trig function, just let me know.

[juan47899]

what if we want an aprroximate answer not an exact # how would i set up my calculator

[rstallworth12]

@juan47899

Hit "SHIFT", "MODE", then select "2" (for LINEIO). That should do it! :-)

[MrKnnknn]

Thanks for these great videos, you are clear and have a great voice.

The issue with the exact vs. approximation is due to the key itself, even if you use the same key but choose 2 (sqrt of) and do sqrt of 48, you will not get the exact result 4 SQRTof2, you will get 6.928.....

[rstallworth12]

@MrKnnknn, if you wish to get the exact square root value, you can try resetting your calculator. Try these steps:

Hit "SHIFT", then "9", then "3", then "=", then "=" again.

Now when you type in sqrt(48), you should get 4sqrt(3). Let me know if this doesn't work.