Questions tagged [gre-exam]
For questions relevant to the general or subject-specific Graduate Record Examination, abbreviated GRE.
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Math Subject GRE 1268 Question 55
If $a$ and $b$ are positive numbers, what is the value of $\displaystyle \int_0^\infty \frac{e^{ax}-e^{bx}}{(1+e^{ax})(1+e^{bx})}dx$.
A: $0$
B: $1$
C: $a-b$
D: $(a-b)\log 2$
E: $\frac{a-b}{ab}\...
CommunityBot
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GRE - Standard Deviation Question (Quantitative Comparasion)
Each video game that a video game shop sold last year was either for the PS4 or Xbox One. The shop sold new PS4 Games for USD 60 and new Xbox One Games for USD 30. The standard deviation for all of ...
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Find Area of Similar Right Triangle
Need help to approach following from GRE study guide
Here is what I have so far
$area = 1/2 bh$
$area CDE = 1/2 bh = 42 = 21 bh$
$AD = 3CD$
Honestly, I'm not sure how to approach. Please give ...
0
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1
answer
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Distance and Arc Length (Math GRE)
A circular helix in $xyz$-space has the following parametric equations, where $\theta \in \mathbb{R}$.
$x(\theta)= 5\cos(\theta)$
$y(\theta)=5\sin(\theta)$
$z(\theta)=\theta$
Let $L(\theta)$ be the ...
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1
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Finite sum inequality (math GRE subject)
Which of the following statements are true:
There exists a constants $C$ such that $\log x \leq C\sqrt x$ for all $x\geq1$
There exists a constant $C$ such that $\sum_{k=1}^nk^2 \leq Cn^2$ for all ...
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Approximate Binomial Distribution using normal distribution
When I was reading "cracking the GRE mathematics subject test" 4th edition page 282, there is a formula regarding approximation of binomial distribution:
In X ~ Binomial(n, p), when n is ...
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If $f(x)=p \sin x + q x \cos x + x^2$ and $f(2)=3$, find $f(-2)$
A GRE subject trig question:
Let $p,q$ be constants and let $$f(x)=p \sin x + q x \cos x + x^2$$ for all real numbers $x$. If $f(2)=3$, find $f(-2)$.
So I plug in and obtain
$$3=\phantom{-}p \sin 2 +...
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Evaluating ${\int_{0}^{1}\sqrt{1+\frac{1}{3x}}\text{ d}x}$ using $\int f^{-1}(x)dx=x f^{-1}(x)-F(f^{-1}(x))+C$
While studying, I countered problem $\text{#}2$ here. $\text{(UCHICAGO REU 2019 - MATH GRE PREP: WEEK 2)}$.
I saw this also. But wanted to know if my way is also correct (regardless of the time ...
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Is this a valid way to compute $\int_{0}^{\infty}\frac{\cos(\alpha x)-\cos(\beta x)}{x}\text{d}x$?
I am not sure if the following way is valid to evaluate
$$\int_{0}^{\infty}\frac{\cos(\alpha x)-\cos(\beta x)}{x}\text{d}x$$
SOURCE
I saw this and this
But I am asking if the following is valid or not?...
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Average question GRE
The average daily temperature from 9th to 16th January(both inclusive) was 38.6 C and that from the 10th to 17th January(inclusive) was 39.2 C. what was the temperature on 17th January?
I am able to ...
CommunityBot
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How $5^{40} < 4^{60} < 27^{30}$, $8^{1/11} < 9^{1/10} < 10^{1/9}$, $e^{e} < \pi^{e} < e^{\pi}$, and $200^{100} < 200! < 100^{200}$?
The following four problems appeared in (UCLA) (University of California, Los Angeles) - GRE Preparation.
$\mathbf{Problem} \space \mathbf{11}, \mathbf{Problem} \space \mathbf{12}, \mathbf{Problem} \...
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Finding relative extrema
For the following problem, we are asked which of the following statements is true for $f(x,y)=x^2-2xy+y^3$
A) $f$ has all its relative extrema on the line $y=x$
B) $f$ has all its relative extrema on ...
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Derivation of the "Combined Work Formula"
Before I get to my question, some background:
Person $A$ can paint a fence at the rate $9 \frac{hour}{fence}$ (or equivalently $\frac{1}{9} \frac{fence}{hour}$)
Person $B$ can paint a fence at the ...
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recommending books for GRE math subject test
I wonder if anyone could recommend some books (other than Princeton Review) to prepare for the GRE math subject exam. I've heard that the REA books have lots of typos, though it has 6 practice exams. ...
1
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1
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If a $3\times 3$ matrix satisfies $A^3-A^2-A+I=0$, then it is not necessarily diagonalisable.
If a $3\times 3$ matrix satisfies $A^3-A^2-A+I=0$, then it is not necessarily diagonalisable.
I have a counterexample
$\begin{pmatrix}1&1&0\\0&1&0\\0&0&1\end{pmatrix}$. But I ...
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Showing that $AB$ is a subgroup.
I was trying to solve this question:
Let $G$ be a group and $A,B$ subgroups of $G.$ Define $AB$ as the set of all products $ab,$ where $a \in A$ and $b \in B.$ Prove that $AB$ is a subgroup of $G$ iff ...
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Matrix in $M_2(\mathbf{R})$ of order $2$ has trace $0$
I found this question in a GRE math subject test from 1987. It's problem 61 at http://web.math.ucsb.edu/~padraic/ucsb_2014_15/math_gre_w2015/GRE_8767_test.pdf. It boils down to the following.
Prove ...
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GRE Subject Test - Past Papers, Books, Advice
This is not for the Maths part of the General GRE. This is for the GRE Subject Test in Maths. Feel free to add or comment.
How do I know the definition of rings or of anything on the GRE given that ...
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Determining the maximum value of a multivariable function under 4 inequality constraints.(Math GRE subject test 9768 Q.25)
I know that I should use Lagrange multiplier method, but how with the inequality constraints? could anyone help me please?
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$u=f(x,y)$ and the partial derivatives are themselves differentiable functions of $x$ and $y$ (Typo?)
I am really not sure whether this question can be posted in MSE or not, but hopefully can be. If not, kindly do not downvote, but suggest me to delete it from here and post it somewhere else.
While ...
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Let $h$ be the function defined by $h(x)=\int_{0}^{x^2}e^{x+t}dt$ for all real numbers $x$. Then $h'(1)=\dots$
This question appeared in the GRE MATH SUBJECT TEST (GR$0568$) - Question# $24$:
Let $h$ be the function defined by $h(x)=\int_{0}^{x^2}e^{x+t}dt$ for all real numbers $x$. Then $h'(1)=$
(A) $e-1$
(...
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1
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Possible dimensions of $V \cap W$ in $\mathbb{R}^n$
If $V$ and $W$ are two dimensional subspaces of $\mathbb{R}^n$, what are the possible dimensions of $V \cap W$ if;
$V$ and $W$ have the same dimensions? (for example; $\dim(V)=2, \dim(W)=2, n=3$)
$V$ ...
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The order of $C=\sum_{k=0}^{90}(90-k)\cos(k ^{\circ}), S=\sum_{k=0}^{90}(90-k)\sin(k ^{\circ})$, and $T=\sum_{k=0}^{90}(90-k)\tan(k ^{\circ})$.
This is multiple choice questions, where using calculators is not allowed. Candidates have, on average, $2$ minutes $30$ seconds to solve it.
MY ATTEMPT:
$k ^{\circ} = (\text{positive constant} \...
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GRE problem involving LCD, prime factorization, and sets.
I think this problem was a bit tricky and I'm trying to better think through this. Here is the problem:
Let S be the set of all positive integers n such that $n^2$ is a multiple of both 24 and 108. ...
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2
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Let $P$ be a polynomial with integer coefficients satisfying $P(0)=1, P(1)=3, P'(0)=-1, P'(1)=10$. What is the minimum possible degree of $P$?
I am preparing for GRE MATH SUBJECT TEST, I have reviewed many problems, some of these problems are not in GRE Math Practice books, but they are in some other books. I found the following problem, but ...
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The possible remainders when a multiple of 4 is divided by 6, and when a multiple of 2 is divided by 3
I'm currently studying for the GRE and a specific type of question has me stumped. I have a two part question, but first here is one problem and my work:
"If x is the remainder when a multiple of 4 ...
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Math Subject GRE 1268 Problem 64 Flux of Vector Field
What is the value of the flux of the vector field F, defined on $R^3$ by $F(x,y,z) = (x,y,z)$ through the surface $z=\sqrt{1-x^2-y^2}$ oriented with upward-pointing normal vector field?
$$\begin{...
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Is $\text{for}\ n\in \mathbb{N},\dfrac{u_{n+1}}{u_n}=q \iff \text{for}\ n\in \mathbb{N},u_{n+1}=q u_n$?
In the correction of bac exams in my country , The Correction Committee ordered us to give the whole point for students who they showed that the sequence $u_n$ is geometric using $u_{n+1}=q u_n$ ...
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What is the greatest integer that divides $p^4-1$ for every prime number $p$ greater than $5$?
What is the greatest integer that divides $p^4-1$ for every prime number $p > 5$? This was on a practice math GRE so it's probably really easy.
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Determining the value of the product of a matrix A with another known matrix without knowing what is the matrix A (math GRE subject test 9768 Q.43)
I have given the entries of the matrix the names $a$,$b$,$c$,$\dots$,$i$, and I multiplied the matrix by the given $2$ matrices. But the problem is that I have for every $3$ entries $2$ equation in $3$...
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Are there 3 or 4 quartiles? 99 or 100 percentiles?
So I understand that a quartile is a quantile where the data is divided into four groups.
1 2 3
---|---|---|---
And 1, 2, and 3 are the quartiles. The ...
CommunityBot
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Find the limit involving a Riemann sum.
Evaluate the two limits.
$$ \lim_{n\to \infty} \left(\frac1n\right)^{15}\sum_{k=1}^nk^{15} \tag{1} $$
$$ \lim_{n\to \infty} \left(\frac1n\right)^{17}\sum_{k=1}^nk^{15} \tag{2}$$
can anyone please ...
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GRE Practice Question
I need a calculus refresher! This question was one of the lowest percent correct on the practice (27%).
A curve in the xy-plane is given by
\begin{align*}
x &= t^2+2t \\
y &= 3t^4+4t^3
\end{...
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How to multiply decimal with wholenumber?
How Can I multiply
x = (0.35)(80)
x = 28
steps by step fastest way
I am not going to lie, but it is time for me to take a test without using a calculator.
Schools have made me worse by giving us a ...
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$\log x =Cx^4$ has only one root. Find C
$\log x =Cx^4$ has only one root. Find C.
I don't know how to solve this problem. Do you take derivative on both sides?
I am thinking C equals 0. Am I correct on that?
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function that preserves compactness
Let S be a compact topological space, let T be a topological space, and let f be a function from
S onto T . Which of the following conditions on f is the weakest sufficient condition to guarantee
...
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Minimum area of Inscribed Square
GRE study guide asks
The perimeter of square S is 40. Square T is inscribed in square S.
What is the least possible area of square T?
Choices are
45
48
49
50
52
They say answer is 50. How do ...
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GRE Reasoning problem time/distance/average speed
David drove to work at an average (arithmetic mean) speed of 45 miles per hour. After work, David drove home at an average speed of 60 miles per hour. If David spent a total of 2 hours commuting to ...
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Divisiblilty & Prime Problems [GRE]
if j is divisible by 12 and 10, is j divisible by 24?
Answer by either saying yes, no , or Can't be determined.
I approached this question as follow:
First i found the prime factors of both ...
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Tricky Question from GRE using Ratios
Of two kinds of alloy, silver and copper are contained in the ratio of $5:1$ and the other in $7:2$. What weights of the two alloys should be melted and mixed together so as to makeup a $5$ lb mass ...
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If p and q are prime which elements are in the subgroup? (GRE question)
I was just doing some practice problems in my abstract algebra book trying to get a warm up this morning, but I found a GRE problem in the problem set and I don't know how to solve it. I've tried to ...
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How many 3-digit positive integers are odd and do not contain digit 5?
It is a GRE question. And it has been answered here. But I still want to ask it again, just to know why I am wrong.
The correct is 288.
My idea is, first I get the total number of 3-digit integers ...
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4
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Among the following, which is closest to $\sqrt{0.016}$?
Among the following, which is closest in value to $\sqrt{0.016}$?
A. $0.4$
B. $0.04$
C. $0.2$
D. $0.02$
E. $0.13$
My Approach:
$(\frac{16}{1000})^\frac{1}{2} = (\frac{4}{250})^\frac{1}{2} = \...
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GRE combination problem $877$.
A computer password must be $5$ characters long. The first character must be a capital letter. The second character must be one of eight specified symbols. Each of the fourth and fifth characters can ...
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Counting numbers in a sequence - explain "Add $1$ before you're done" rule
I'm studying for the GRE, and my study book uses a rule that it never justifies for counting numbers in a sequence: "Add $1$ before you're done."
For example, how many multiples of $3$ are between $...
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If $A$ is a subset of the real line $\mathbb R$ and $A$ contains each rational number, which of the following must be true?
The question and its answer is given in the following picture:
Subject GRE 0568 Exam Q.52
Question 52.
If $A$ is a subset of the real line $\mathbb R$ and $A$ contains each rational number, ...
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3
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GRE Statistics Problem
Matt gets \$1000 commission on a big sale.This commission alone raises his average commission by \$150. if Matt's new average commission is $400, how many sales has Matt made?
I feel this question is ...
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7
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Finding a number given its remainder when divided by other numbers
I have this GRE question that I'd like to know how to solve. I want to solve it in as simple a way as possible, since it is GRE material. In particular, I don't want to use "congruences" or modulo ...
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Answering a question containing $\sqrt{1.5}$ without using calculator.
Of the following which is the best approximation of $\sqrt{1.5}(266)^{\frac{3}{2}}$?
(A)1,000
(B)2,700
(C)3,200
(D)4,100
(E)5,300
How can I answer this without using a calculator and in about 2....
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Show mean of a sequence of sets is zero but mean of countably infinite set is infinity if increasing
Let $\Omega$ be a countably infinite set, and let $F$ consist of all subsets of $\Omega$. Define $\mu(A) = 0$ if $A$ is finite and $\mu(A) = \infty$ if $A$ is infinite. Show that $\Omega$ is the limit ...
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