 # High school math questions and answers

Recent questions in Secondary America Ware 2022-05-24 Answered

### Sample Variance in Principal Components AnalysisI was reading this Why is the eigenvector of a covariance matrix equal to a principal component?. And in the top answer, the poster mentions that if the covariance matrix of the original data points ${x}_{i}$ was $\sum$, the variance of the new data points is just ${u}^{T}\Sigma u$. I'm not sure why this is the case. Could someone enlighten me? seiyakou2005n1 2022-05-24 Answered

### E.g. the equation is$u\left(x\right)=f\left(x\right){u}^{\prime }\left(x\right)$Is there a general form of solving such an equation?If not, is there a general form for $f\left(x\right)$ being a linear function? Hugo Brady 2022-05-24 Answered

### How do you solve and graph $4\ge k+3$ ? Kendrick Pierce 2022-05-24 Answered

### How to derive $\mathrm{sin}\left(2x\right)=\frac{1}{\sqrt{1+{\mathrm{cot}}^{2}\left(2x\right)}}$? Janiyah Huffman 2022-05-24 Answered

### How do you express intervals as inequalities such as [3,8)? Hyus Jsjs 2022-05-23

###  Rohit Rawat 2022-05-23

### According to one survey in India, 75% of Instagram users love REELS. Suppose that 25Instagram users (randomly selected) have been approached in the university located in vileparle. They have been asked about their status of like/ dislike the Instagram- REELS.a) What is the probability that Exactly 15 of them would agree with the claim (or said theylove Insta-REELS)?b) What is the probability that Exactly 20 of them would agree with the claim (or said theylove Insta-REELS)? zintekensci 2022-05-23 Answered

### Find all 4 roots of the polynomial:$f\left(x\right)={x}^{4}+2{x}^{3}-x-1.$ Alani Conner 2022-05-23 Answered

### For which value(s) of parameter m is there a solution for this system$\left\{\begin{array}{l}mx+y=m\\ mx+2y=1\\ 2x+my=m+1\end{array}$when does this system of equations have a solution? raulgallerjv 2022-05-23 Answered

### To find minimum value of $2\mathrm{csc}\left(2x\right)+\mathrm{sec}\left(x\right)+\mathrm{csc}\left(x\right)$ Case Nixon 2022-05-23 Answered

### Suppose that $x$, $y$ and $z$ are three integers (positive,negative or zero) such that we get the following relationships simultaneously1. $x+y=1-z$and2. ${x}^{3}+{y}^{3}=1-{z}^{2}$Find all such $x$, $y$ and $z$. Janiyah Huffman 2022-05-23 Answered

### Bookkeeping is mainly concerned with a. All options are correct. b. Interpreting the data. c. Recording the economic activities. d. Designing the systems for recording, classifying and summarizing. Aditya Erickson 2022-05-23 Answered

### Use the identities$\mathrm{cos}2x=2{\mathrm{cos}}^{2}x-1=1-2{\mathrm{sin}}^{2}x$$\mathrm{sin}x=\mathrm{cos}\left(\frac{\pi }{2}-x\right)$to help evaluate${\int }_{0}^{\pi /2}\sqrt{1-\mathrm{sin}x}\phantom{\rule{thickmathspace}{0ex}}dx$ Nicholas Cruz 2022-05-23 Answered

### Show that every irrational number in $\mathbb{R}$ is the limit of a sequence of rational numbers. Every rational number in $\mathbb{R}$ is the limit of a sequence of irrational numbers. Camille Flynn 2022-05-23 Answered

### How do you solve $4<13+r$ Andy Erickson 2022-05-23 Answered

### For any even $n$, say $n=2m$, a row complete Latin square of order $n$ can be formed by writing down$0,1,2m-1,2,2m-2,3,\dots ,m+1,m$as the first row and then developing subsequent rows by adding $1$ modulo $n$.I'm not quite clear on how that goes, such as what the difference is between $2m$ and $m$. $2m$ stands for $n$, does $m$ stand for modulo? I'd like to see and example with an even number or two, such as $4$, and $6$.I tried, $2m=4$$0,1,3,2,2\dots$wait, that can't be right. Bailee Landry 2022-05-23 Answered

### I was following along a Y-T video proving that there is no useful measure on the power set of $\mathbb{R}$. The proof is too long to lay out here but I'm certain that most respondents here will recognize it if I just describe it.The proof starts by pulling all the rational numbers from (0,1], creating little `boxes' along the interval. Next construct a set A that contains one and only one point from each box. Then create a sequence, ${A}_{n}$ by adding a rational r from (-1,1), jogging A left and right in (-1,2]. Then we take the countable union of the ${A}_{n}$, and here's where I lose the plot. The claim, setting up the final blow in the proof, is that(0,1] $\subseteq \left\{\cup {A}_{n},n\in \mathbb{N}\right\}\subseteq \left(-1,2\right]$I get the RHS but the LHS looks exactly wrong to me. (0,1] contains all the reals and by construction the term in the middle is devoid of the rational numbers. How can the term in the middle contain (0,1]? Eliaszowyr1 2022-05-23 Answered

### A Web music store offers two versions of a popular song. The size of the standard version is 2.4 megabytes. The size of the high-quality version is 4.6 MB. Yesterday, the high-quality version was downloaded twice as often as the standard version. The total size downloaded for the two versions was 2668 MB. How many downloads of the standard version were there? istupilo8k 2022-05-23 Answered

### Can $\frac{2u\mathrm{sin}\left(\alpha -\beta \right)}{g\mathrm{cos}\beta }=\frac{u\mathrm{cos}\left(\alpha -\beta \right)}{g\mathrm{sin}\beta }$ be reduced to $2\mathrm{tan}\left(\alpha -\beta \right)\mathrm{tan}\beta =1$?The closest I can get is:$\mathrm{tan}\alpha \mathrm{tan}\beta -2{\mathrm{tan}}^{2}\beta =1$Is this correct so far? Cara Duke 2022-05-23 Answered

### Graph the following system of inequalities. Show (by shading in) the feasible region.$x+2y\le 12$$2x+y\le 12$$x\ge 0,y\ge 0$

Turning back to high school math can be essential to understand engineering tasks that you may encounter later. The high school math problems have all the basics that have good equations and answers, which will let you see things clearly. The list of high school math questions below will help you identify your weaknesses and find various solutions. Taking a look at high school math equations, you will see certain parts that can be applied to Physics. In either case, the best way is to learn by example, which is why high school math problems with answers will be essential.