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#201 Re: Help Me ! » Synthetic Division » 2023-10-03 02:08:32
Hi there. I am currently in the review section of my college algebra textbook in my self-study journey. Section R.6 covers Synthetic Division.
Divide 0.1x^3 + 0.2x by x + 1.1
add a term for the missing power:
0.1x^3 + 0x^2 + 0.2x + 0
do the synethtic division setup
synthetic division:
-1.1 | 0.1 0.0 0.2 0.0
|
-----------------then do the steps
synthetic division:
-1.1 | 0.1 0.00 0.200 0.0000
| -0.11 0.121 -0.3531
--------------------------
0.1 -0.11 0.321 -0.3531#202 Re: Help Me ! » Solve for D » 2023-10-02 02:53:46
The important thing when copying an image url is that the link you're copying must refer to an 'image address' (ie, with an 'image extension' as above), not something else like a 'link address'.
Btw, the direct Imgur url to an actual image begins https://i.imgur.com... ('i.' signifying it's an image link, I suppose).
This is the URL of the image: https://i.imgur.com/t8F77rc.png
Note that it starts with https://i.imgur.com and ends with an image extension (png, in this case).
And from the image in my post #14:
"Tip: The URL starts with https://i.imgur.com, and ends with an ‘image extension’ (eg, ‘gif’, ‘jpeg’, ‘jpg’ or ‘png’)."Your https://imgur.com/gallery/4Gh1VYy doesn't start with https://i.imgur.com, and doesn't end with an image extension...
on a mobile the image extension doesn't show up and the uri starts 'https://imgur.io'
the image file itself is at https://i.imgur.io/7uB3NEI_d.webp? with a query string after the query mark
#203 Re: Help Me ! » Show Trinomial Is Prime » 2023-09-30 03:23:13
I've tried a number of reliable maths sites and none have a concept 'quadratic prime'.
i think it means prime polynomial
thats any polynomial that isn't factorable over the integers
so x^2+1 is prime, but x^2-1 isn't
#204 Re: Help Me ! » Solve for D » 2023-09-29 08:11:38
Nothing pops up telling me to select image in new tab.
I also don't see _d in my url. Back to the drawing board.
so apparently its browser-specific
on my android it works using the 'carbon' browser
it doesn't work using 'samsung internet' browser
what're you using?
#205 Re: Help Me ! » Future Time » 2023-09-29 07:06:00
Let me see.
12,997 ÷ 24 = 541.54166666667
541 x 24 = 12,984
12,997 - 12,984 = 13
so there are 13 hrs left over after taking the 541 full days out
What time (CST) will it be 12,997 later?
I say 1pm.
You say?
yeah
12 hrs after noon is midnight
1 hr after midnight is 1am
#206 Re: Help Me ! » Difference of Cubes » 2023-09-29 06:56:45
...my work and answer.
looks good to me
also they both multiply out to the same thing
#207 Re: Help Me ! » Show Trinomial Is Prime » 2023-09-29 06:52:01
I came across an interesting question in Section R.5 for which Sullivan does not provide a sample question for.
Show that x^2 + x + 1 is prime.
has the book covered the quadratic formula yet?
if yes, then set equal to zero and show quadratic formula has no real solutions
if no, then use that x^2 = x*x and 1 = 1*1 so any factors have to be (x [sign] 1)
try (x - 1)(x - 1), (x + 1)(x + 1), and (x + 1)(x - 1)
when none of them works then quadratic is prime
#208 Re: Help Me ! » Solve for D » 2023-09-29 04:23:19
Everything I do online is done on my android cell phone which is a few years old. Get it?
got it
so i got this to work on my not new android:
go to the page with your image
long-press until a menu pops up
select 'open image in new tab' (or new window)
go to the url
delete the _d and anything after that
replace with .jpeg
(yes it has to be jpEg, not jpg)
copy the corrected link into your post
hope that helps
(if it doesnt please say where it goes wrong
i'm home sick and so bored
youd be doing me a favor giving me somthing to do)
#209 Re: Help Me ! » Rational Number » 2023-09-29 04:14:32
Bob wrote:If you have a recurring decimal it is always possible to turn it into a fraction.
eg.
0.16161616......
let a/b = 0.16161616.....
100a/b = 16.16161616.....
Subtract
99a/b = 16a/b = 16/99
I do have one question.
You said subtract but there is no subtraction symbol in your work.
its hard to show without formatting
subtracting
a/b = 0.16161616...
100(a/b) = 16.16161616...
100(a/b) = 16.16161616...
-1(a/b) = -0.16161616...
-------------------------
99(a/b) = 16
a/b = 16/99#210 Re: Help Me ! » Extra Factor Completely » 2023-09-29 04:03:29
Bob wrote:I used Wolfram Alpha https://www.wolframalpha.com/input?i=fa … 2+-+x+-+2+
and it has no easy factors. Are you sure you have it copied correctly?
Yes, the question is exactly as stated in the book.
Here are the instructions:
Factor completely. If the polynomial cannot be factored, say it is prime.
This is question 119 in the textbook.
The textbook answer is (x - 1)(x + 1)(x + 2).
if you multiply that back out you get
you factored pairs to get to here
but these dont have common factors so nothing can be pulled out front
i think the book typoed the first minus; it was supposed to be plus
#211 Re: Help Me ! » Difference of Cubes » 2023-09-29 03:57:46
There is no difference between the formula you provided and the textbook x^3 - a^3 = (x - a)(x^2 + ax + a^2). So, I don't understand your comment about me being confused. I didn't go further in my work.
Let x = (3x - 2)
the line above is where you use "x" to mean 2 different things: the placeholder in the factorisation formula and also the variable from the original expression
taken literally it says
When I plug this into your formula and Sullivan's formula, I get stop when I see the answer is something completely different that the answer posted in the back of the textbook.
weird
what are you getting?
let formula be
you have
so plug in
#212 Re: Help Me ! » Solve for r » 2023-09-29 03:49:05
its a even-index root (4) so it needs a plus minus in front
#213 Re: Help Me ! » Solve for D » 2023-09-29 03:45:30
Copy and paste to see question and math work.
https://imgur.com/gallery/6mjyDcd
im on a laptop
i did right-click on image
'open image in new tab'
got url with file extension: https://i.imgur.com/t5wC8Hg.jpeg
wrapped in img tags
i think it works
btw: put plus minus on square root
#214 Re: Help Me ! » Future Time » 2023-09-29 03:28:58
The current time is 12 noon CST. What time (CST) will it be 12,997 hours from now?
The question looks easy enough but it's tricky to me.
I know there are 24 hours in a day. So, I decided to divide 12,996 by 24 hours, which yield the decimal number 541.54166666667.
Of course, this decimal number tells me nothing.
it tells how many days are included in 12996 hrs: 541 days
so 541*24 is how many whole days
subtract from 12996
(did you divide 24 into 12997)
A. How do I find the correct answer?
B. If the quotient found leads to the right answer, can you show me how?
however many hrs are left over after subtracting you add to 'noon' to get the time.
#215 Re: Help Me ! » More Factor Completely » 2023-09-27 06:51:31
Ok. Thanks. Now, I am having a hard uploading images to the site.
Here is a question about Even, Odd ,Neither.
The image is found here:
putting in img tags doesnt work
a. i think the 1st fcn is y = 1/x (imnshp, when they don't give you fcn its kind of unfair to tell you to find stuff out about it)
"even" means it matches on both sides of the y axis
"odd" means it matches on both sides of diagonal y = x
this fcn is odd because you can fold graph on diagonal and teh 2 halfs will match
domain is x not equal to 0 (im guessing from the graph; it looks like there is a vertical asymptiote at x=0)
range is y not equal to 0 (im guessing from the graphl it looks like there is a horizontal asymptote at y=0)
b. it looks like maybe an exponential, like y=e^x ?
if you fold the graph on the y axis the halfs wont match so its not even
if you fold on the diagonal the halfs wont match so its not odd
domain looks like all x
i dont know how your supposed to know the range from the picture; the graph could cross the axis off to the left
but if you guess that the graph close to the center tells you everything you need to know then it looks like graph is always above x axis
#216 Re: Help Me ! » Factor Completely » 2023-09-26 06:59:50
Rewrite x^6 as (x^3)^2.
Let u = x^3
u^2 + 2u + 1
Factor.
(u + 1)(u + 1)
Back-substitute for u.
(x^3 + 1)(x^3 +1)
The sum of cubes tells me that (x^3 + 1) is the same thing as
(x + 1)(x^2 - x + 1).My answer is (x + 1)(x^2 - x + 1)^2.
Textbook answer is (x + 1)^2(x^2 - x + 1)^2.
Who is right and why?
in the red part you have
in the blue part you factored
then replace
the aquare goes on both factors inside
once you do that youll match the books answer
#217 Re: Help Me ! » Number Needed to Complete the Square » 2023-09-26 06:53:29
Bob wrote:The two expressions have p^2 in it and 2ap if you put a = 7
So add a^2 = 49 and you have a perfect square.
Let me see.
(14/2)^2 = (7)^2 = 49
The missing number that completes the square is 49.
You say?
yes that is what he said
#219 Re: Help Me ! » Factor Completely » 2023-09-25 14:31:05
Factor completely. If the polynomial cannot be factored, say it is prime.
x^6 + 2x^3 + 1
We're in luck here because (x^3)^2 = x^6
You said we're in luck in this case because (x^3)^2 = x^6.
What if the question is not so obvious? What then?
then maybe it cant be factored, right?
if your doing perfect sqares then it has to fit into perfect aquare pattern
#220 Re: Jai Ganesh's Puzzles » 10 second questions » 2023-09-25 06:50:06
Once again, I wish to inform you post once a day, not more. Strictly.
sry; can't find this in forum rules??
rule applys to hwole forum or is help me excepted?
thnx
(post for 25 sep 2023)
#221 Re: Jai Ganesh's Puzzles » 10 second questions » 2023-09-23 23:48:38
#8918.
#222 Re: Exercises » Compute the solution: » 2023-09-23 18:04:31
909.
#223 Re: Jai Ganesh's Puzzles » Oral puzzles » 2023-09-23 17:59:41
#5923.
#224 Re: Jai Ganesh's Puzzles » 10 second questions » 2023-09-23 17:58:13
#8917.
#225 Re: Help Me ! » Find the Number » 2023-09-23 16:53:41
I am thinking of a number. It lies between 1 and 10; it's square is rational and also lies between 1 and 10. The number is larger than pi. Correct to 2 decimal places (that is, truncated to two decimal places) name the number.
ne # between these works
infinitely many others do 2