Hello and welcome to HD Calcs
I'm Rick and today we're gonna have a look at how we can use the memory function to Store and Recall variables
on the Texas Instruments BA II plus calculator
to do that we'll be using the STO key that looks like this, located here
the RCL key that looks like this located here
the second function key that looks like this located here
and the zero key with the second function of memory it looks like this located down here
now this calculator has 10 memory slots
one for each number key so 0 to 9 are each a memory slot
we can store a variable in them by placing it on the screen so there's 10
then pressing the STO key and then choosing a key we want to store it in
so let's put this 10 into memory slot 0
you won't see any indication on the screen other than a little decimal that appears after the number there letting you know it's been stored.
You can also store the result of calculations
so if for example we go 1 divided by 2 equals we get 0.5
and we can store that into memory slot number 1
again by pressing STO 1
there we go.
Now if you want to recall a number from the memory slot you press RCL and then choose the slot you want to use
so let's recall that 10 from the first slide by pressing 0
and there we go we see the 10 has appeared on our screen
we can also add and subtract numbers from memory slots so let's add that point 5 from memory slot 1
we do that by pressing + recall 1 there's that 0.5, equals
and you can see we have 10.5 now
and you can store that into memory slot 2
you can view what you have stored in memory by pressing the 2nd, zero key which is the memory key
and that will bring you to this screen
here we see M0 which is memory slot zero has a 10 in it
if we scroll down we see memory slot one has 0.5
scroll down again memory slot 2 has 10.5 remember that's where we stored that
and if we keep scrolling we see that all our the memory slots have zero or nothing stored in them
and we keep going and we come back to 0 and 10
we can clear these memory slots by pressing 2nd, CE or Clear Work
which will clean the memory slots but not get rid of anything else
so we press that, now we see M0 is equal to 0
and if we keep scrolling through we'll see all our memories are 0
and we're ready to store new numbers in there
You can also overwrite memory slots without clearing all of them
by just storing over that single memory slot
so remember if we had let's say 10 stored in 0
and our 0.5 stored in 1
there we go 10 and 0.5
and we only want it to overwrite our memory slot 0
you can just enter a new number in there let's say 2, STO, 0
and if we check our memory again you see memory slot 0 is 2
but we still have our 0.5 in memory slot 1
Storing and Recalling values is really handy on this calculator if you want to do any long or complicated calculation
because it lets you store complicated numbers without having to type them in over and over
An example of this would be say using Pythagoras to solve for a right angle triangle
So for example if we wanted to solve this right angle triangle
and we know that A squared plus B squared equals C squared
and can be re-written as the square root of A squared plus B squared equals C
and we want to solve for our C unknown side.
What we can do is store our two known sides as A and B
so let's store 4 as our A
4, Store, into zero let's say.
and 3 into slot number 1 as our B
so 3, Store, 1
There we go, and we can view our memory to confirm that's in there, yeah
4 and 3 looks good
now we can just enter this in as a formula
so if we go A squared
which we can get by recalling 0 which is our 4 squared
plus B squared which was, recall our number 1
there we go, squared
adding them together and then square rooting the whole thing
we see we get a result of 5 which is our C
and solves our triangle for us!
All right I hope this helps and good luck on those tests up there everybody!