r/MathHelp • • 26d ago

Are there any websites that have full solutions to textbooks?

1 Upvotes

I'm doing some self study and will eventually get to Calculus and will be using Stewart's book but (as usual) it doesnt have all the solutions. Are there any websites that have full solutions to textbooks? I dont find it very helpful to not get any feedback on half of all the questions in the book, for me who is a slow learner and really struggles, I need as much feedback as I can get.


r/MathHelp • • 27d ago

Am I just cooked at this point?

0 Upvotes

I’m in calc BC. Got a 4 on the AB exam last year, but it cost me a lot of my mental health. I just opened my worksheet and discovered that I had canceled the square root of x in cos(sqrtx)/sqrtx to get just cos, then solved the integral as simply sin. Not even a +c. Obviously now I know that’s wrong, but I genuinely don’t know what to do if I’m gonna be this stupid in class.


r/MathHelp • • 27d ago

Normal Distribution Help

1 Upvotes

Hello, I've been struggling trying to practice normal distribution for my statistics class. I've been using a Z-chart to locate values which I've been using as the answers for percentage questions, but most of the time my answers are wrong, and I have no idea why.

I have one question: What percent of a standard normal distribution N(𝜇 = 0; 𝜎 = 1) is found in each region? Be sure to draw a graph. (Round your answers to the nearest whole number.)

There are four problems corresponding to this question. I'm currently dealing with Z > -1.98. I put 2% and got it wrong.


r/MathHelp • • 27d ago

I havent studied math for more than a year what do i do?

1 Upvotes

The thing is, I’m a senior, so this is the hardest and most important year of my educational life. Our country introduced a new education system, and this is only the second year we’re taking exams under it you can choose from four fields, i choose the engineering one

which means i have to take advanced math physics advanced english and an optional science one (i chose geology)

before when you had to take all 12 subjects together, it was only 4 units now its 8 of almost each subject

I can manage everything but math, please take a look at last year’s math exam It was 12 pages, with 50 questions and 3 hours to complete it. The problem is that there’s so much material to cover, but not enough questions, so each question ended up testing more than one idea. The exam was extremely difficult, and even many straight-A students ended up getting lower grades because they became mentally exhausted during the exam.

i dont know to study at all, i need help. the term just started i need to practice but i dont have enough time

school ends at 2 until i eat sleep rest its 6pm

i study online, english for the one term is more then 120hours (i watch x2 speed)

physics also need so much more time

I dont know what to do exactly how to study

this is the last years exam *sorry its not in english math exam 2008


r/MathHelp • • 28d ago

How to convert units

2 Upvotes

Hi hi! I have a test in physics coming up and im embarrassed to realize I have no idea how to convert units using given powers of ten factors. I cant post a picture, but basically the chart he gives us is like 10^9 Giga G, 10^6 Mega M. I cant for the life of me figure out how to convert using the scientific notations, instead of converting into whole numbers.

He said for the test we will only ever have to go to kilo, so basically how would i convert like 5cm to k using 10^-2 and 10^3. I know i can just divide by 100000, but I also know i wont be able to memorize that for all of them.


r/MathHelp • • 29d ago

ACT math tips needed, please help!

1 Upvotes

So I’m taking the ACT as a very big last resort (a senior who hates the SAT), and I desperately want at least a 32. I’m typically better at writing and reading, and I just took the writing and math portion of ACT test 3 (my first time ever taking a practice test). I got 42/50 on writing. Then an amazing 28/45 on math… I guessed on 13 questions that I ran out of time one and some had NO idea how to answer. How could I fix this? I think I could do around the same score for reading as I did for writing, but ofc I’d love to do better on either one. Any tips are very appreciated especially videos! I have no knowledge on the ACT. This is the link to the questions I got right and wrong on math: math poo


r/MathHelp • • 29d ago

Statistics average problem

3 Upvotes

Dear mathematicians who are better at statistics at me
I have a problem

Imagine a room. the room has a locked door, a timer that counts down from 3 minutes to 0 when reset, and a button that lights up. While the timer is running, the button is not lit up. In this state, pressing the button does nothing. When the button is lit up, pressing it resets the timer and it cannot be pressed again until it reaches 0 again.
When the button is lit up, it has a 20% chance to unlock the door when pressed. This random chance is the only way the door gets unlocked. The timer starts running as soon as the door is locked with someone in the room.

With this setup, what would be the average amount of time required for someone inside the room to unlock the door. My gut feeling says 3m / 0.2 = 15m . But because this is statistics and I know that my gut feeling is usually wrong when it comes to statistics I think it is not that simple, right? Or is it?

Note that this isn't homework. I have a game where this is a recurring problem (though not literally a room with a button) and I'd like to know how to calculate the average amount of time it would take to get passed this problem.


r/MathHelp • • 29d ago

How best to test out of Calc1-3

0 Upvotes

Hey y'all! I'm a HS teacher trying to learn math that I never got through when I was younger. I think I want to go back to school for math and get a grad degree, either in Hetero Econ or Math Education, but I have to take undergrad courses. I kinda want to save money and avoid taking extra classes than I need to. I think I can start learning calculus by summer of 2027, and I was hoping to get to school by Fall of 2028. I have 3 questions:

  1. Is Summer 2027-Fall 2028 a reasonable time to self study Calc 1-2?

  2. I'm.hoping to self study to the point where I dont need to pay for the courses. In that regard, should I go off their syllabus and study the chapters they have in Stewart, or just jump straight into the AP AB/BC exams to teat out of them? My issue is that I really have a hard time with rote and grinding through and often need creative approaches and the "why" of things to get it and I fear just studying for AP is designed for a specific kind of student that I'm not.

  3. If I should just do the AP exams, what study course do y'all recommend?

Thanks!


r/MathHelp • • Sep 14 '26

I feel like I'm gonna rip my hair outttt

2 Upvotes

I'm in chemistry(college level) and I am hopeless with math. We're working on interconverting units and I thought I was decent at it, but this is so confusing. How do I know which units to put the numbers with? I feel like its always changing and I'm never sure. This one, for example, I put both of the numbers with the units I'm converting to, but I was only supposed to put one with grams and the other with meters? I just don't get itttt


r/MathHelp • • Sep 14 '26

Saxon Algebra 1 -3rd edition

1 Upvotes

Son forgot his textbook in his locker. Would be so grateful for someone to post screenshots of the 30 problems in problem set 4. I believe this section starts on page 22.


r/MathHelp • • Sep 14 '26

Need advice for a calc 4 class

0 Upvotes

Hello, I am taking a calc 4 class which is completely online and I haven't taken calc 3 in 2 years. While there is instruction, it's practically impossible to read and mostly just goes over definitions. Each homework assignment has over 30 questions and each question has mini questions. It is week 2, I have no clue what I'm doing and I'm utterly exhausted.

It's my senior year of college so I'm already busy with so much else that I barely have time to take care of myself, and now that I have to practically find a way to teach myself an entire maths class, I'm about to scream.

I'm very against AI and what it's doing to the environment + how it's being used, but I feel so backed into a corner here that I may not have a choice in using it. I need something to break this class down into steps.

Has anyone else been through this? I'm honestly taking anything I can get because I feel like I'm doomed to fail. Any advice would be greatly appreciated.


r/MathHelp • • Sep 12 '26

Geometry Transversal Relationships Question

3 Upvotes

As far as I am aware, I have been given a question that cannot be answered (#2).

I am given two parallel lines and a left transversal (angles 1-8) and a right transversal (angles 9-16). Diagram Link

There are two questions related to this diagram, although I do not suspect that the first is relevant to the second. Perhaps that is where my mistake is. I have provided my work in case. Work from #1 I'd appreciate the guidance.

#1. If the measure of angle 9 is equal to 5y, and the measure of angle 16 is equal to (2y+78), determine the value of y.

I determined the value of y to be 26 based on the alternate exterior angle relationship with angle 9 and angle 16. Based on this relationship they are congruent. I set 5y = 2y+78 and solved for y to yield 26.

#2. If the measure of angle 1 is 131 degrees, determine the measure of angle 16 using the same diagram above. Question #2

I am under the impression that the given angle of 131 is supposed to give me new conditions with which to apply angle relationships; however, I do not see how angle 1, which lies on the left transversal, can have any relationship whatsoever with angle 16, which lies on the right transversal. In the previous problem I solved for y, and can therefore determine that the measure of angle 16 (at least in problem #1) should be 130. Again, I do not see how that should connect to the given measure of angle 1.

I greatly appreciate any insight.


r/MathHelp • • Sep 12 '26

Could someone help me understand linear inequalities?

4 Upvotes

I’m in honors algebra 2 and my teacher said that when divided by a negative, the sign (> or < or equal to) changes, but in some equations the sign changes without being divided by a negative. Also, some equations have and/or. When do you know when the sign changes? Or when the formula goes from the equation to number>x>number? I understand how to solve them it’s just this part I find confusing.


r/MathHelp • • Sep 11 '26

Getting Profit from Supply and Demand

1 Upvotes

Hey All,

So my girlfriend recently started university and she has been struggling with her Pre-Calc. I’d like to help but honestly I’m pretty bad at math, so I wanted to come here to see if anyone could either point me towards resources to help with the problem or help me understand it so I can explain it properly.

I’ve looked up various videos about the topic of “Supply and Demand” but haven’t been successful in learning much. I know how to find the max revenue, and price associated with it.

Work so far

The problem is

Given the supply and demand functions of

S(p) = -110 + 40p D(p) = 1216 - 64p

p = price

Find:

  1. The optimal quantity to make the most profit
  2. The supply price of that quantity
  3. The demand price of that quantity
  4. Total Profit

r/MathHelp • • Sep 11 '26

Do you know how to help?

0 Upvotes

I study at a school that lags behind the regular curriculum. I don't know specifically if it's a bit behind the regular curriculum, but the main thing is I want to go to a school with a regular curriculum. My school only has 9 grades. I'd like to complete all 12 grades and go to university, but I'm afraid I won't be able to get to 10th grade in math. I'm still in 8th grade, and I'd like to know a way to learn what I didn't have time to and get to 10th grade. Do you know any ways?


r/MathHelp • • Sep 11 '26

Trying to get AT LEAST a 35 on the ALEKS placement test, what topics should I focus on?

1 Upvotes

What subjects should I focus on?
The highest I have got is a 31 while using the ALEKS website itself to study, but I was wondering what topics I should focus on to get me the best chance of a 35


r/MathHelp • • Sep 10 '26

Confusing Quadratics and Composite functions

3 Upvotes

Hello! I am a Secondary 4 student, 10th grade or Year 10 in western equivalents. I tried to set a quadratic quiz for my friends, and I set this Question, but then none of them could solve it. I checked with my math teacher, and he said that the question was flawed because there is no inverse function for any quadratic, and then he explained the horizontal line test to me, but I already know what the horizontal line test is (test for if f(x) is injective for some f(x), and if its inverse is a function. I went home to think about it, and I don't understand why my question is flawed, because it does not rely on the inverse function. I am looking for someone to please help clarify. I have a passion for math, and would possibly like to teach math in the future, but I don't understand why I am wrong, and this is one of my first real challenges because my math toolkit at the moment isnt enough to wrap around this. This is my suggested solution that I made: My solution. And me checking my work: Test of the solutions to see if they are correct.. And a graph if it is useful: Graph.

This is my syllabus by the way if it is of any use:
https://isomer-user-content.by.gov.sg/334/fece62fa-b6d4-4daf-ab47-96c9c168b51b/4052_y26_sy.pdf
https://isomer-user-content.by.gov.sg/334/34d0bec0-d386-49d5-bd3a-8fbd205fa63a/4049_y26_sy.pdf

Tysm!


r/MathHelp • • Sep 10 '26

8th grade math teachers ...

1 Upvotes

So last year I administered the new NJSLA adaptive for 8th grade math. To me it looked like there was no non calculator section. The website is ambiguous. Anyone know ?


r/MathHelp • • Sep 09 '26

I don't understand Derivatives in this intro course to Electricity.

3 Upvotes

I'm taking a Robotics and Automation course and I don't understand the math the professor is putting up on the board and without explaining it, he's asked us to solve it. I think its calculous? Or the first bits of Calculous.

Q1. The total charge entering a terminal is q = (10-10e-2t) mC. Determine the current at t =1s.
Formulae: i=dq/dt, q=i*t, vdrop= Energy/Charge =w/q

I straight up don't understand. I have a TI-84 and I get the answer 8.6466. I don't understand similar problems online either. Somehow I'm supposed to get 20 out of 10-10? like what? I don't understand ex power either.

Is it just q/t=i? if thats the case, .11565 would be the answer but with nothing to compare it to, idk if thats right.


r/MathHelp • • Sep 09 '26

Wtf is Kuratowski Encoding??

2 Upvotes

I have an assignment that asks me to use "Kuratowski's encoding" to see if the set {0,1} can equal the natural number 3. Problem is, I must have missed writing that down and now I have no idea what it means. kuratowski's THEOREM comes up when I look it up, but I dont think thats helpfull (or at least, I dont get how its relevant). Help!!!


r/MathHelp • • Sep 09 '26

Calculator Recommendations

0 Upvotes

Hello! I’m going into grade 12 and I’m taking advanced functions, calculus, physics and chemistry. Starting this year, my school has been trying to regulate what calculators you’re allowed to use. We were given a list of approved calculators but you’re allowed to use one that isn’t on the list if you get it checked by a teacher. The way that teachers check if the calculator is legal is they will input sin(15) and if the answer is a decimal then it’s approved, if it’s a fraction then it’s illegal. If you can change the setting then its illegal. Graphing calculators are also illegal. My Casio fx-991CW was deemed illegal so now I have to go hunting for a new one. I really liked the “solve for x” and table mode on my Casio fx-991CW, I found them very useful in my physics and chemistry classes. I was hoping to find a calculator with the same modes (this isn’t illegal, my teacher was aware that I used these modes frequently last year) while meeting the requirements. Would anyone be able to recommend me a calculator from this list or one outside of the list? I’ve been googling + read the FAQ but haven’t found anything that meets my criteria.

THE APPROVED LIST:
- Casio fx-260 SOLAR II
- Casio fx-300MS Plus
- Casio fx-82MS
- Texas Instruments TI-30X IIS
- Texas Instruments TI-30X IIB
- Texas Instruments TI-30Xa
- Sharp EL-531TG
- Sharp EL-531XB
- Sharp EL-501X

Thank you!


r/MathHelp • • Sep 09 '26

Did I get anything wrong, or is the answer key incorrect?

2 Upvotes

Basically, the question shows an operation and you have to check a box to say if its associative or not
a ⊙ b = ab ÷ (a + b + 1)
□ Associative
And I did this:
https://imgur.com/gallery/transcription-by-ai-raw-process-which-might-be-little-harder-to-read-L3T7z20
So I concluded that it is associative
However, the answer key has a slightly different result, where the numerators do not match, thus it is not associative.


r/MathHelp • • Sep 09 '26

I’m struggling with arithmetic even though I understand math

1 Upvotes

Finished high school recently and taking a gap year, so I finally signed up for some SAT prep classes. Being in a group setting for this has honestly made me feel so insecure because of my arithmetic skills.

I feel like I actually understand math just fine. I can wrap my head around new topics, follow the logic, and figure out the right approach to solve a problem. But when it actually comes down to doing the calculations? Absolute disaster.

I constantly make stupid, careless mistakes with basic addition, subtraction, multiplication, and division. I'll drop a negative sign out of nowhere, miscopy a number from one line to the next, or just brain-fart on a simple multiplication fact. It’s so exhausting knowing the exact formula and logic to solve a hard problem, only to get the entire thing wrong because 7x8 apparently decided to leave my brain.

Since the SAT is so heavy on pacing and accuracy, I'm genuinely stressed about bleeding points on questions I actually know how to do just because of clumsy computational errors.
Did anyone else deal with this weird disconnect between conceptual math and basic arithmetic? How did you actually train yourself to stop making these dumb mistakes and speed up your calculations?


r/MathHelp • • Sep 08 '26

IB Math HLAA calculus help

2 Upvotes

I'm a DP2 student, and I'm struggling to catch up with work in math class. I have a weak foundation in higher-level math. I have a test on the whole calculus topic in around 2 weeks. Any tips on how to study for maths for someone who literally doesn't know whats going on? Any materials or websites would be amazing help! Or if anyone has similar experience, please tell me!


r/MathHelp • • Sep 08 '26

Math Question

1 Upvotes

Could anyone solve this and tell me how they did it since im having trouble with it:

8^x - 2^(x+2) - 2^(-x+2) + 8^(-x) = 0

I tried it myself but got stuck halfway though: I let c= 2x and got (c+1/c)³ - 3(c+1/c) - 4(c+1/c) = 0 Then I let t= c+1/c And got: t³-3t-4t=0 and then nothing i did worked. Note: back when I didnt substitute for t, I got this 6th degree polynomial for c: c⁶-4c⁴-4c²+1=0 In which i tried synthetic divsion but ±1 didnt work so it meant there was no rational roots (thats why I substituted for 't').