All Answers 358512 Answers

You still didn't tell me what PRB stands for!

Fractions on the calculator:  

This is a page that Kitty put together for us a little while ago.  Once again - thanks Kitty<3 

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In answer to all those people who want to know how to do fractions on this calculator:

Here are some of the replies from various answers; I hope they can help you out:

Re: How do you do fractions on this calculator?

"5 and a half - 8 and a quarter would be

$$\left({\mathtt{5}}{\mathtt{\,\small\textbf+\,}}{\frac{{\mathtt{1}}}{{\mathtt{2}}}}\right){\mathtt{\,-\,}}\left({\mathtt{8}}{\mathtt{\,\small\textbf+\,}}{\frac{{\mathtt{1}}}{{\mathtt{4}}}}\right) = -{\mathtt{2.75}}$$ "(by Melody)

Re: where is the fraction button

"It is a box above a box" (by Anonymous)

"On many calculators out guest is correct. There is no fraction button on the Web2.0calc  You have to use the $$\div$$ button. To enter 3 and 1/2 - 6 and a quarter you would press

$$(3+1\div2)-(6+1\div 4)=$$" (by Melody)

Re: How do we use fractions on this calculator??

"with the $$\div$$ button. If you are doing calculations with mixed numerals it is best to put them in brackets like $$(3+1\div 2)$$" (by Melody)

"You can use forward slash / as we write in a fraction. 6/2 is a fraction. And if there are more numerals involved, use brackets as (6*2+8)/4

I hope it helps." (by novice)

"you simply make it a decmil if 4 were 1/4 i would put 4.25" (by Gman2598)

Thanks to everyone who answered!

Let's see if I remember any of Cal II

I believe that since we're expanding about 0 that we have a Maclaurin series. The expansion of this is given by

Sometimes, the most tedious thing about this activity (as you have probably discovered) is taking the derivatives. Let's do that for the first few terms and see if we can arrive at a "pattern".

f(0) = 1 - cos(0^2) =1- cos(0) = 1- 1 = 0

f'(x) = 2xsin(x^2)    f'(0) = 0

f"(x) = 2sin(x^2) + 4x^2cos(x^2)       f"'(0) = 0

f'''(x) = -8x^3sin(x^2) + 12xcos(x^2)     f'''(0) = 0

f''''(x) = -48x^2sin(x^2) - 16^4cos(x^2) + 12cos(x^2)       f''''(0) = 12

At this point, we can probably stop.

So far, the only term is     (12)x^4 / 4!    =    (x^4) /2

Taking successive derivatives (very tedious, indeed) until we reached f⁸(x) would yield  "0' terms

From an online app, the next non-zero terms occur at f⁸(x), f¹²(x), and f¹⁶(x) - as we might now expect.

 

So it appears that we have this .....

I'm experimenting

$$\underset{\,\,\,\,{\textcolor[rgb]{0.66,0.66,0.66}{\rightarrow {\mathtt{x}}}}}{{solve}}{\left({\mathtt{3}}={\mathtt{4}}{\mathtt{\,\times\,}}{\mathtt{x}}{\mathtt{\,\small\textbf+\,}}{\mathtt{1}}\right)} = \underset{{\tiny{\text{Error: Unknown Function 'solve'}}}}{\underset{\,\,\,\,{\textcolor[rgb]{0.66,0.66,0.66}{\rightarrow {\mathtt{x}}}}}{{solve}}{\left({\mathtt{3}}={\mathtt{4}}{\mathtt{\,\times\,}}{\mathtt{x}}{\mathtt{\,\small\textbf+\,}}{\mathtt{1}}\right)}}$$

No it doesn't work straight from the forum!

You have to do it from the calculator itself.

What a pity!

Thanks for showing us that admin I like the new fraction calc too!!

1. x=1/2

2. x=2/3

3. x=-7

Go to the site calculator

press $$2\:x^y\:6=$$

and you wil have your answer.

OR

$$2^6 = 2\times2 \times 2 \times 2\times 2\times 2 \\
2,4,8,16,32,64
=64$$

answer is 64 

Great post...If I could, I'd give it a "thumbs-up and a finger"  .....no, not THAT finger !!!

I think "Anonymous" likes to remain, well, Anonymous

His sign-off Reluctantly Modern Old Geezer, acronym-wise, is RMOG..... which = Real Men Of Genius

He neglected one fine detail......some older calculators also had a PBJ button.....however, they were discontinued mainly because they cost more bread and often got the user into a jam.

Re: (1+i)^16/(1-i)^15

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Let's simplify these separately.  We need to remember how to write complex numbers in exponential form. This is given by:

And

Where      z= ( a + bi)       r= l z l = √(a² + b²)       tan^-1(b/a) = θ

Let's do the first one

z= (1 + i)   r = √(1² + 1²)  = √2     tan^-1(1/1) = π/4

So we have  (√2)¹⁶ e^{i 16(π/4)}   = (√2)¹⁶ e^{i (4π)}  =  (2)⁸ [ cos (4π) + i sin (4π)] = 128 [1 + 0i] = 128

The second one (1 - i) is similar except that tan^-1(-1/1) = -π/4

(√2)¹⁵ e^{i 15(-π/4)}   = (√2)¹⁵ e^{i (-15π/4)}  =  (√2)¹⁵ [ cos (-15π/4) + i sin (-15π/4)] =

64√2[ (1/√2) + (1/√2) i ] = 64 (1 + i)

Putting all this together, we have  (128) / [64 ( 1 + i)] = 2/(1 +i) and multiplying by the conjugate (1 -i) on top and bottom, we have  [2 (1- i)] /2 = (1 - i)

Whew!!.....that was a lot of work just for that, huh?

I just realised that you have put this question up twice and you now have two very different (both probably correct although I haven't checked) answers.

One below by problem - thank you problem and welcome to the forum. (I already left a private welcome message for you, you may need to press on your username to get into the message centre)

and one from admin instructing you how to use the calculator.

Both good answers.

Please don't post questions twice,  it just fills up the forum with 'spam'.

What a fabulous post.   (But, what does PRB stand for?)

Why didn't you identify yourself?

That was hilarious.

For the young people: Francis was a talking mule.  The movies were very funny.

This site has a great calculator; just enter 522/18 :)

http://web2.0calc.com/

Assuming you mean tan^-1 (arctan), just click "2nd" in the top right corner of the calculator. Then click the key where "tan" was, and it will have changed to arctan.

Below is this sites calculator:

http://web2.0calc.com/

It will show up as atan(  . Then enter your number, end the parentheses, and click the equal sign/press enter to solve:)

Why does my (oldish) Texas Instruments not have a PRB button?

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It would be unusual for old TI to have that button. You would have to go way back to find that button on any machine. My 1947 Burroughs advanced differential adding machine had one (See photo). Of course, this unit came with the optional complex matrix integrator, and statistical processing system, that might be why.

By the early 1970s with the electronic calculators, these options were no longer available – it could not even do a simple square root, let alone generate complex solutions.

Doing that was worse than replacing vacuum tubes with transistors; don’t even get me started on integrated circuits. Another thing, just as bad: the libraries replaced the card catalogs with the new-fangled electronic lookup machines. I really enjoyed separating cards, stuck together from gooey fingers and careless sneezes. God, I miss those days!

It was a conspiracy; I tell you … A real conspiracy! But they couldn’t take my slide rule away from me. No sir! I was smart – I hid it in my sock. Pretty sneaky, wasn’t it? 

Finally, in the last few months the electronic technology is starting to catch-up to the advanced mechanical technology of the 1930s and 40s. It is still not as good, though. The PRB button on those old machines is still more advanced than any PRB button on modern machines.

So, if you want to find a PRB button on an older unit, you will have to go back 60 or more years, everything in-between are the very dark ages.

I wish they still made parts for those Burroughs adding machines. It’s no wonder us old geezers live in the past. I miss the good old days.

Giddy-up, Frances, else we ain’t gonna make it home before dark.

Reluctantly Modern Old Geezer

2.4513570781

use the formula -16t²+(velocity)t+the height of the ball

t=time

I truly hate the result from the site calculator.

The result, x=4, is correct, but the presentation, saying that both sides of the original equation  are equal to x and equal to 4 is most certainly not correct.

you can switch to "fraction calculator" in the highlighted menu:

you can use the built in "equation solver" to verify your solutions:

7x-2=-1

7x=-1-(-2)

7x=-1+2

7x=1

x=1/7

Eg:

1 over 4 is "1/4"

4 over 1 is 4/1" 

"/" is the divide sign for the calculator

4=6x+5

4-5=6x

-1=6x

x=-1/6

I have no idea what you are talking about.

$${\frac{{\mathtt{4}}{\mathtt{\,\times\,}}{\mathtt{x}}}{{\mathtt{5}}}}{\mathtt{\,-\,}}{\frac{{\mathtt{3}}{\mathtt{\,\times\,}}{\mathtt{x}}}{{\mathtt{4}}}} = {\frac{{\mathtt{3}}{\mathtt{\,\times\,}}{\mathtt{x}}}{{\mathtt{10}}}}{\mathtt{\,-\,}}{\mathtt{1}} = {\mathtt{x}} = {\mathtt{4}}$$

That is the answer straight from the site calculator. I putit in using Math(Input=result) tab.

Now I'll do it by hand - When you do it you should line up all the equal signs.

I multiplied by 20 because 20 is  the LCD Lowest common denominator and that got rid of all the fractions.

$$\frac{4x}{5}-\frac{3x}{4}=\frac{3x}{10}-1\\\\
20\times \left(\frac{4x}{5}-\frac{3x}{4}\right)=20\times
\left(\frac{3x}{10}-1\right)\\\\
16x-15x=6x-20\\\\
x=6x-20\\\\
-5x=-20\\\\
x=4$$

100m²    

@@ End of Day Wrap - Saturday 3/5/14   Sydney, Australia Time 23:30

Hi all,

Great answers today from DavidQD, Admin, CPhill, Rom, Gib, Bertie and of course some anonymous people. Thank you all.  

We noe have an outbox so we can see the messages that we have sent.  That's a nice step forward.  Other asspects of the members section still need a lot of work.  Not to worry, it is comming together slowly.  Our top answer board has changed again.  The numbers have had another boost. lol  Andre has told me that it has 'bug' so I don't know what it will look like tomorrow.

I did send a quick message to Andre.  I told him of Alans's observations concerning the member profiles appearing in the answer section.  I also asked him if he could run some kind of language scanner through posts so that some of the vulgar ones could be deleted automatically.  He hasn't replied yet.

We had an anonymous post signed "Lucifer van Pelt" this morning.  It was a lot of fun.  Take a look for yourself.