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#51 Re: Help Me ! » Equation of the Circle...Again » 2024-02-29 09:49:39

FelizNYC wrote:

TWO LOVES

1. MATHEMATICS

2. CLASSICAL GUITAR HYMNS

Hi, solo_guitar!
big_smile

#52 Re: Help Me ! » Help me! » 2024-02-29 09:48:16

RyanSnyder wrote:

I'm struggling with understanding the proof for the Pythagorean Theorem. Could someone break it down step by step?

there are loads of different proofs
Can you give a link (or just type out) the proof that you're looking at?
Thnx!
big_smile

#53 Re: Help Me ! » What make you fascinated » 2024-02-29 09:47:14

What level are you starting at?
beginning algebra?
pre-algebra?
calculus?
big_smile

#54 Re: Help Me ! » Inverse Functions. Why rewrite as y=f(x) » 2024-02-29 09:45:52

paulb203 wrote:

Inverse Functions. Why rewrite as y = f(x)?

What does this mean? And does it have to be y?

Youre working with inverse functions which means that you started with a function f(x)
(it doesn't have to be 'f(x)'; it can be g(x), h(x), etc; f(x) is the most common name)
Its easier to do the algebra to find the inverse when you rename f(x) as y
youre finding the inverse function so you solve for x in terms of y
then you swap the variables and rename the new y as f^(-1)(x)
but whatever the name for the function -- y, f(x), f^(-1)(x), Q(x) -- its all the same thing
You pick the value for the input (almost always x) and figure out the value of the output (which you graph on the vertical axis)

#55 Re: Help Me ! » Find GCF » 2024-02-29 09:39:20

FelizNYC wrote:

Find the GCF of 45 and 75.

Another way is to do the prime factorization w/ a table:

factors
 45: 3 * 3 * 5
 75: 3     * 5 * 5
---+--------------
GCF: 3     * 5    = 15

#56 Re: Help Me ! » Find Factors » 2024-02-29 09:35:48

FelizNYC wrote:

You know, the AI Questions app tells me that the factors are 1, 2, 3, 4, 6, x, 2x, 4x, 6x. I also know that my work is correct. Who's right?

you did the factoring right
But you didn't put things back together in *all* the possible ways
AI is many times stupid at math
But it is right-er this time
All the factors are:
1, 2, 3, 4, 6, 12, 1x, 2x, 3x, 4x, 6x, 12x, 1x^2, 2x^2, 3x^2, 4x^2, 6x^2, 12x^2

#57 Re: Help Me ! » What is the surface area of a circle? » 2024-02-29 09:30:53

paulb203 wrote:

Not the area of a circle, but the surface area of a circle.

a circle is in the plane so it's flat
It doesnt have a 'surface' to have an area of

#58 Re: Help Me ! » How to write √8 in the form 2^n » 2024-01-29 03:11:36

paulb203 wrote:

which equals 2^1*2^(1/2)

which equals 2^1+(1/2)

almost: add grouping symbols to keep the 1/2 in the power:

2^{1 + (1/2)}

#59 Re: Help Me ! » Euclid book 1 of elements proposition 28 » 2024-01-26 08:56:03

your line on th eleft is leaning right so its less than 90 deg
100 deg would lean left

#60 Re: Help Me ! » Straight line graphs » 2024-01-04 10:45:56

paulb203 wrote:

Is the equation for a straight line graph always in the form y=mx+c?

It doesn't have to be; it can be Ax+By+C=0 or other alternates-- but they can all be solved for y= to get y=mx+b

paulb203 wrote:

If so, is an equation for a straight line such as y=4 shorthand for y=0x+4?

Exactly-- and writing it your way emphasizes that the slope is zero so the line is horizontal.

#61 Re: Help Me ! » Functions. Is g(x) etc, the OUTPUT? » 2023-12-31 07:55:47

g(x)=y
g(4)="y, when x=4"
output=result-of-relationship-formula, given input

#64 Re: Help Me ! » 3 (at least) definitions of 'angle' ?!?! » 2023-12-20 02:22:53

paulb203 wrote:

...defintition for intersect: "To cross over (have some common point)"

The first part (to cross over) seems to imply cross and continue, yeah?
Whereas the second part (have some common point) suggests that to "meet" or "just touch" would satisfy the criteria, yeah?

Agree

paulb203 wrote:

Q. Is it incorrect to say, for example, "Angle x is 45 degrees"?

Technically, yes, I think
but everybody uses this lingo & everybody understands what yu mean

paulb203 wrote:

Q. Would it be more correct to say, "The measure of angle x is 45 degrees"?

agree

#67 Re: Help Me ! » Method for; 3^c=1/ √3 ? » 2023-12-18 09:33:25

paulb203 wrote:

I’m looking for the proper method...for 3^c=1/ √3 ?

Remember that sqrt is 1/2 power & flipping is minus
1/sqrt{3}=1/(3^(1/2))=3^{-(1/2)}
so c=-1/2
Always try to convert sides to same base
Then set powers equal and solve - no guessing
big_smile

#68 Re: Help Me ! » What is the method for; 3^a = 1/9 Solve for a. ? » 2023-12-18 09:28:40

paulb203 wrote:

Q. But presumably this only works if the numerator of the fraction on the right is a square of the integer value on the left (9 is a square of 3; 16 is a square of 4; and 4 is a square of 2)?

Not necessarily
You could have something like 4^n=8
so switch to (2^2)^n = 2^(2n) and 8 = 2^3
2n=3
n=3/2
But yeh it has to be the same base somehow (or else logs, i think)

#70 Re: Help Me ! » 3 (at least) definitions of 'angle' ?!?! » 2023-12-17 08:34:46

paulb203 wrote:

Q. Do the lines (arms) in the MIFun illustration intersect? Or merely meet/join, at the vertex?

"intersect" doesn't have to mean "cross and continue"
It can mean "meet" or "just touch" like a repeated root of a quadratic just touches the x-axis

#71 Re: Puzzles and Games » Find the missing number in the series: 190, 94, 46, 22, ..., 4 » 2023-12-09 17:58:12

nice!
I like how there can be many ans to these things
and theyre all equally good!
up

#72 Re: Help Me ! » Gap in understanding Taylor series » 2023-12-08 05:33:48

Zeos wrote:

I've been studying in Khan academy: AP®︎/College Calculus AB and then also AP®︎/College Calculus BC.

Up until the sub-unit I'm in right now, which is: Finding Taylor polynomial approximations of functions, which is inside Unit 10: Infinite sequences and series, I've felt that everything taught to me all the way back to the beginning, which for me, took many months of studying, all material was taught from a fundamental perspective. There was nothing that was just laid out as facts to memorize, without explaining the full process that motivationally build up to a mathematical concept.

Suddenly i watch the Taylor series first videos and i think that I've unintentionally skipped several videos before it, but presumably no.

Yes, i feel that i understood all the material in Unit 10: Infinite sequences and series, up to that point, but no, i'm far from fully understanding what is thrown at me here.

(a) What is this? (b) Why do this expansion? (c) How this has developed into this polynomial structure? (d) What are the most basic examples that brought this concept into development? (e) When is this helpful?

Even when going into a Google and YouTube and Open AI to search, i couldn't find an explanation that felt to me is a ground up explanation.

The only explanation i could find, which also seems to be only partially intuitive and partially ground up is:

[MEDIA=medium]6b3a703ae084[/MEDIA]

nothing is showing up in your 'media' link

Zeos wrote:

(f) Taylor series helps when trying to solve more complex functions? (g) Like which functions? (h) Like Sin or Exponent functions? (i) Then why is it that the polynomial that approximates these functions, is built from the exact same functions that make the complexity problem in the first place? (j) In which way are these functions complex to solve? (k) In what way do they present a complexity problem that raises or raised the need to develop the Taylor polynomial structure? (l) Why is the saying that this is the way computers calculate some functions come into context?

(m) And how was that polynomial structure discovered and developed in the first place? (n) Why does this polynomial structure approximate other functions? (o) How was the mechanics of this structure developed? (p) What's the whole thing with the factorial and why does the word normalization come into context?

(q) How come i go through a course for many months and everything seems more or less explained to me at an intuitive level and then suddenly at once, there is such a gap in the level and depth of explanation?

(r) Have i reached some transparent mysterious gate in the studies of mathematics, where only people with higher IQ than me are allowed to continue through?

You posted 16 questions; could you maybe narrow it down to 1 or 2? (I labeled them for reference)

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