Questions tagged [gre-exam]
For questions relevant to the general or subject-specific Graduate Record Examination, abbreviated GRE.
389
questions
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17 views
$u=f(x,y)$ 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 ...
1
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1answer
58 views
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) $e-1$
(...
1
vote
1answer
32 views
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; $\dim(V)=2, \dim(W)=2, n=3$)
$V$ ...
0
votes
1answer
24 views
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} \...
1
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2answers
53 views
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 ...
0
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2answers
134 views
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 $u_{n+1}=q u_n$ ...
2
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2answers
220 views
Preimage of Closed Set Under a Continuous Map Isn't Closed?
Problem: In the $xy$-plane, the graph of $x^{\log y} = y^{\log x}$ is
(A) Empty
(B) A single point
(C) A ray in the open first quadrant
(D) A closed curve
(E) The open first quadrant
Here is ...
2
votes
2answers
817 views
Integral of the Product of a Function and Its Derivative
Problem: Let $f$ be a function such that the graph of $f$ is a semicircle $S$ with end points $(a,0)$ and $(b,0)$, where $a < b$. The improper integral $\int_{a}^{b} f(x) f'(x) dx$ is
(A) ...
1
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2answers
66 views
For what values of t does the eigenvalues $\lambda_1$,$\lambda_2$ has the value $\lambda_1$+$\lambda_2$ = 1.
Do not know how to solve it, could anyone help me please?
0
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2answers
48 views
Determining the number of gallons of fuel that the car used on the trip.
My answer was (C), where I was thinking while I was solving how the unit could be Gallons only, but the correct answer is (A), I do not know why my answer is wrong and why (A) is the correct answer, ...
2
votes
1answer
3k views
Is this Enough for the Math Subject GRE? [closed]
I have been studying for the math GRE for quite sometime now. I have been going through the princeton review and old GRE tests, and in fact without much very difficulty at all. As a way of getting ...
0
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2answers
92 views
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 $3$...
0
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0answers
119 views
Does the math subject GRE exam contains a graph paper and a calculator or no.
I know that the math subject GRE exam is a paper based test, but does this paper contains a graph paper? I also have read(not sure from the source) that calculators are not allowed on this test, even ...
0
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1answer
69 views
Knowing 3 points of a figure, the fourth point can take how many values so that the given figure form a parallelogram. (GRE exam 9768 Q.42)
I do not know how to solve it, could anyone give me a hint? or tell me if this question How to test whether a set of four points can form a parallelogram is useful in the solution or irrelevant?
0
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2answers
48 views
Determining the relative maximum of a 2 variable function in less than 2.5 minuites.(GRE Exam 9768 Q.41)
I know that I have to calculate the gradient of $f$, equate it to zero to find the critical points, calculate A,B,C,$\vartriangle$, then if $\vartriangle$ < 0 & A < 0 then f has relative(...
2
votes
2answers
1k views
Closure in the Discrete Topology
If $\tau$ is the discrete topology on the real numbers, find the closure of $(a,b)$
Here is the solution from the back of my book:
Since the discrete topology contains all subsets of $\Bbb{R}$, ...
1
vote
1answer
347 views
Cauchy Number of a Permutation
Find the Cauchy number for the permutation $(1354)(267)$.
I did a google search on the definition of a Cauchy number, but nothing really came up. This is the best I could find, but it is rather ...
0
votes
3answers
212 views
Calculating the probability that more of a fair coin tosses will result in heads than in tails.
My thought was the probability is: $\frac{5}{8} + \frac{6}{8} + \frac{7}{8} + 1$ and the sum is $\frac{13}{4}$ but this is not one of the choices. and the correct answer is E. I do not know why my ...
3
votes
1answer
126 views
Domain of the Function Defined in Terms of a Series
The domain of the function $f(x) = \int (x+2x^2 + 3x^3 + ...)dx$ is...
I just want to find out whether the method I used to arrive at the solution is valid. In finding the domain, I first noted that $...
-1
votes
2answers
153 views
The greatest value of Riemann sum and integral of a function on the interval [0,10]
My answer was D, but the correct answer is B, I do not no why my answer is wrong and why B is the correct answer and why other answers are wrong. Could anyone explain this for me?
0
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2answers
683 views
Matrix Representation of a Bilinear Form
Let $b : \Bbb{R}^2 \times \Bbb{R}^2 \to \Bbb{R}$ be the bilinear form defined by $$b((x_1,x_2),(y_1,y_2)) = x_1 y_1 - 2x_1 y_2 + x_2 y_1 + 3x_2 y_2.$$ Find the $2 \times 2$ matrix $B$ of $b$ relative ...
0
votes
4answers
101 views
How can I solve this question without using calculator and in only 2.5 minuites.
This is a math subject GRE exam question, that I know how to solve but in more than 2.5 minuets and using a calculator, may be there is some intuition for solving this question that I do not know that ...
2
votes
2answers
106 views
Solution to Integral Equation
Which of the following is a solution of $u(x) = x + \int_{0}^{x} (t-x)u(t)dt$??
(A) $\sin x$
(B) $x \cos x$
(C) $\ln (x+1)$
(D) $x e^{-x}$
(E) $xe^x$
Since all of the choices are twice differentiable,...
-1
votes
3answers
154 views
For how many values of $x$ are the median and the mean are equal? [closed]
I know how to calculate the mean and the median, but I do not know how to solve this. Could anyone help me please?
-1
votes
1answer
182 views
Calculating the equation of the plane tangent to a given surface in xyz space. [closed]
The solution is written below and I understood all the solution until saying that the value of z is 1, but I do not understand the rest, why z + x = 1, could anyone clarify this for me please ?
-2
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3answers
189 views
Limits at infinity of a function and its derivative [closed]
I do not know how to solve this question, could anyone help me please?
2
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3answers
5k views
Number of integers between 1 and 1000 that are divisible by 30 but not divisible by 16.
I know that the number of integers between 1 and 1000 that are divisible by 30
is 33, and the number of integers between 1 and 1000 that are divisible by 16 is 62, but I do not know how to calculate ...
2
votes
2answers
198 views
Using the rational root test (subject Math GRE exam 9768 Q.31)
I used the rational root test and my answer was B as -5 does not divide 9, but the correct answer is C. Could anyone clarify this for me please?
1
vote
3answers
112 views
Math subject GRE exam 9768 Q.30 (condition that a basis of a real vector space must satisfy)
I am sure that A,B and E are wrong, but I do not know which is right C or D, and why, could anyone help me please?
0
votes
1answer
346 views
Sets Whose Elements Sum to an Even Integer
From the set of integers $\{1,...,9\}$, how many nonempty subsets sum to an even integer.
This is probably trivial for most, but I am notoriously bad at counting, so I just want to make sure I am ...
1
vote
1answer
68 views
Calculating the value of a definite integral knowing the value of the integrand and its derivative on the boundaries.
I do not know how the givens are useful in solving this question:
Could anyone help me please?
0
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3answers
827 views
What is the smallest possible dimension $V_1$ intersection $V_2$ must have.
My answer was $A$ because the two vector spaces may be disjoint and hence intersection is $\{0\}$ whose dimension is zero by convention, but the correct answer is $C$.
Could anyone clarify this for ...
0
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1answer
894 views
Let $f$ be a function such that $f(x) = f(1-x)$ for all real numbers $x$. If $f$ is differentiable everywhere, then $f'(0)$
I do not know how to solve this question:
Could anyone help me please?
0
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3answers
197 views
Math subject GRE test 9768 Q.26
What is the fastest way to solve this question?
I checked and I found that the derivative exists at $x = 1$.
2
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2answers
152 views
Weird GRE mistake [duplicate]
According to the answer key, the correct answer is (a).... This is obviously a mistake, right? If a square matrix is invertible, then it has full rank.
1
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1answer
225 views
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?
0
votes
2answers
280 views
A basis for a subspace of Euclidean 4-space consisting of all vectors orthogonal to 2 vectors.(Math subject GRE 9768 Q.24)
The question is in the following picture:
The answer is C.
I know the method of finding all vectors orthogonal to a vector,but it will take a long time if I applied for 2 vectors, as I must answer ...
0
votes
1answer
51 views
Determining the measure of a central angle in a circle ( subject math GRE exam 9768 Q.23).
The question is given in the following picture:
I know that the triangle ABC will be an isosceles triangle but I do not know how to use this knowledge in the solution, could anyone help me please ?
1
vote
2answers
214 views
Subject GRE math exam 9768 Q.21
The question is given in the following picture:
I started to solve it first by differentiating $ y = \frac{1}{8} x^2 + \frac{1}{2}x + 1$, and I got $y^{'} = \frac{1}{4}x + \frac{1}{2}$, at point (0,1)...
2
votes
1answer
80 views
Subject GRE exam 9768 Q.18
The question is given in the following picture:
My first answer to the question was A. My justification was as follows:
$A(r) = \pi - \pi r^2$ and \begin{equation*}
\lim_{ r \rightarrow 1^-}
\frac{A(...
2
votes
3answers
334 views
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{...
1
vote
3answers
119 views
Subject math GRE exam 9768 Q.17
The question is as follows:
And the answer is E.
I calculated the following:
$\Delta^2f(1) = -6, f(2) = 3, f(3)=1, \Delta f(3)=4.$
Then I stopped and don`t know how to complete because the formula ...
8
votes
4answers
2k views
Math subject GRE Exam 9768 Q.16
The question is in the following picture:
And the answer is (D).
At first I agreed with this answer when I added the given three vectors component wise,but when I added the forth component in ...
4
votes
1answer
1k views
On the difficulty of the new mathematics GRE exam
I have read a lot of various threads on both this website and other website claiming that the GRE mathematics exam has become exceedingly difficult over the years. For example, the document available ...
0
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1answer
91 views
Old GRE probability question
Let $x$ and $y$ be uniformly distributed, independent random variables on $[0,1]$. What is the probability that the distance between $x$ and $y$ is less than $1/2$?
My continuous probability ...
-1
votes
3answers
101 views
Subject GRE exam 9768 Q.12 [closed]
The question is in the given picture :
And the answer is C as shown in the answer sheet below:
But this answer is so strange for me as I know that a set is closed if and only if it contains all ...
3
votes
4answers
695 views
Sketching Parametric Graph of $\sin t$ against $\cos t$ in the Fourth Quadrant
The question is given in the following picture:
The answer is B as shown in the following picture:
But I did not understand why, could anyone explain this for me please?
What confuses me exactly ...
2
votes
3answers
257 views
Math subject GRE exam 9768 Q.6
The question is given in the following picture:
I solved it and my answer was B, but the answer sheet said that the answer is C as you can see from the following picture:
I do not know why, ...
-1
votes
3answers
109 views
Math Subject exam 9768 Q.4 [closed]
The question is given in the following picture:
Could anyone give me a hint please?
-1
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4answers
132 views
Exam $9768$ of subject $ GRE Q1.$ [closed]
This is the question:
Could anyone give me a hint on how can I solve it?
