I am watching this: (https://youtu.be/wCZ1VEmVjVo?t=575) video and at the timestamp, these equations are shown, but I can't really make sense of them. Where do they come from? I usually only know fuctions withou a comma, for example f(x,y) = 3xy + 2x^2 -cos(y). I mean the equations f(x,y) = (f_1(x,y),f_2(x,y)) and f(x,y) = (x^2 -y^2, 3xy). submitted by /u/nostrangertolove69 [visit reddit] [comments ..read more

Suppose ab ≡ 1 (mod n) and n is pseudoprime to base a. Show that n is also pseudoprime to base b. I'm struggling before to start with this one. I think that by definition, b is going to be the inverse of a. I'm trying to figure out how to combine the definition of a pseudo prime with the definition of a Carmichael number to get my desired result. Is there some other definition that I'm missing? Here's what I have so far: Let ab ≡ 1(modn). This means that b is the inverse of a in some base n. We also know that, by definition of pseudoprime, a{n−1} ≡ 1(modn). Since b is the inverse of a, we the ..read more

I’ve been thinking about it and I don’t entirely understand how to go about solving this. I’ve never taken any probability class, so I have some trouble understand the notation. I found the answer on the site I have linked, but the notation E(10H|10H)P(10H)+… kinda goes over my head a little and was wondering if anyone could help me understand, maybe intuitively too :) Thanks! (I’ll link it in the comments) submitted by /u/knogimicks [visit reddit] [comments ..read more

I have found this Runge-Kutta solver https://www.mathstools.com/section/main/runge_kutta_calculator which does exactly what I need except it only has 5 instead of 6 inputs. Does anyone know of an equivalent solver with more inputs? submitted by /u/okapibeear [visit reddit] [comments ..read more

Hi, I did this survey for my project and I' m trying to analyze this one piece of data and I just can't figure it out. People ranked each goal based on importance (most important, moderately important, least important). They all came up with the goals themselves but then I was able to make out 8 (based on similarity) I could assign to each respondent. I am trying to figure out the overall percentage of how important each goal is in the pie of all the different goals. So for example (most important = 3, moderately important = 2, least important =1). Is there any way to work this out so that ea ..read more

I was a bit confused because the answers have to be a radical so I wasn’t sure how to use those to find the other sides https://imgur.com/a/1uPNwy6 submitted by /u/slimshady713 [visit reddit] [comments ..read more

Hi, I’m looking for help on how to solve one and two step linear equations. I just need the algebraic way, not the diagram ways. For example, here’s what I mean by one and two step: One: 3x = 1/2 Two: x/5 + 1/2 = 7/8 I don’t know how to do the problems as fractions or integers. I find it worse when it’s integers though if I do try. Is there any simple understanding or way I can remember a method for both of them? :,) submitted by /u/TrickAd2471 [visit reddit] [comments ..read more

Can not figure out how to get the two x values in the quadratic when y = something other than 0. https://postimg.cc/Xph65X0W How can I work out -4.8 and -0.2 instead of simply drawing lines down and eyeballing it? submitted by /u/MedellinKhan [visit reddit] [comments ..read more

Six times a number is 45 greater than the product of the number and -3. Find the number. 6x=45 45>-3x Is this how I should set up the equation(s)? submitted by /u/ec-vt [visit reddit] [comments ..read more

i’m usually fine at it, but during notes today i got 32 as the length of a leg while everyone else got 15. i’m super confused on why this is! math problem submitted by /u/keiIani [visit reddit] [comments ..read more