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Post New Question
All Questions
+0
230827 Questions
+1
399
1
:( hard
For how many integers $a$ satisfying $1 \le a \le 23$ is it true that $a^{-1} \equiv a \pmod{24}$?
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Guest
Dec 24, 2020
0
527
2
triangle
What is the radius of the circle inscribed in triangle ABC if AB = 5, AC=7, BC=8? Express your answer in simplest radical form.
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Guest
Dec 24, 2020
0
444
1
help plz
Two circles of radius 4 are externally tangent to each other and are internally tangent to a circle of radius 12 at points A and B. Find the distance AB.
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Guest
Dec 24, 2020
0
350
1
+4
I need help D:
Please help me I need this... How many 4 letter words can be constructed of the form cvcv where C is a consonant, V is a vowel and the letter y isn't used? maths
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AdrianAndia999
Dec 24, 2020
0
432
1
geometry
Given a semicircle with diameter 5, three squares are constructed as shown below. Find the sum of the areas of the three squares.
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Guest
Dec 24, 2020
0
527
1
Help!!
I choose a random integer $n$ between $1$ and $10$ inclusive. What is the probability that for the $n$ I chose, there exist no real solutions to the equation $x(x+5) = -n$? Express your answer as a common fraction.
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Guest
Dec 24, 2020
0
747
3
Help! Thanks:)
1. The infinite sequence is defined by and for each integer . What is the remainder when is divided by ?
2. What is the average of all positive integers that have three digits when written in base 5, but two digits when
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Guest
Dec 24, 2020
-1
740
1
+2498
Can anyone explain me this one?
View question - I don't understand how these products hold (0calc.com)
hectictar
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Solveit
Dec 24, 2020
0
257
0
probability
What is the probability that when we roll 5 fair 6-sided dice, at most 4 of them will show 1 or 2?
Guest
Dec 24, 2020
0
510
2
Help!!
What is the remainder when $10!$ is divided by $2^{7}$? (Reminder: If $n$ is a positive integer, then $n!$ stands for the product $1\cdot 2\cdot 3\cdot \cdots \cdot (n-1)\cdot n$.)
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Guest
Dec 24, 2020
0
450
2
new year
Find n so that 20 + 21 + 22 + ... + n = 2021.
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Guest
Dec 24, 2020
0
277
0
inverse function
Let
Find the function k(x) such that f is its own inverse.
Guest
Dec 24, 2020
0
324
1
sum of divisors
The sum of the positive divisors of a positive integer of the form 2p is equal to 600, where p is prime. What is p?
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Guest
Dec 24, 2020
0
324
1
Help is appreciated
If $a,b,c$ are positive integers less than $13$ such that \begin{align*} 2ab+bc+ca&\equiv 0\pmod{13}\\ ab+2bc+ca&\equiv 6abc\pmod{13}\\ ab+bc+2ca&\equiv 8abc\pmod {13} \end{align*}then determine the remainder when $a+b+c$ is divided by $13$.
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Guest
Dec 24, 2020
0
757
1
lattice points
A lattice point is a point whose coordinates are both integers. How many lattice points are on the boundary or inside the region bounded by y = |x| and y = -x^2 + 9?
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Guest
Dec 24, 2020
0
335
1
number theory
The greatest common divisor of two integers is (x+4) and their least common multiple is x(x+4), where x is a positive integer. If one of the integers is 24, what is the smallest possible value of the other one?
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Guest
Dec 24, 2020
0
364
3
What is the answer?
what is the answer to: Find x, y, and z such that x³+y³+z³=k, for each k from 1 to 100
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Guest
Dec 24, 2020
0
385
1
algebra
Define f(x) = (1 + x)/(1 - x) and g(x) = 1/x. Find the value of g(f(g(f(... g(f(12)) ... )))) where there are 16 compositions of the functions g, and f, alternating between the two.
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Guest
Dec 24, 2020
0
405
1
piecewise function
Let
f(x) = 2x + 8 if x <= -3
f(x) = -x^2 - 3x + 1 if x > -3
Find the sum of all values of x such that f(x)=-5.
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Guest
Dec 24, 2020
0
355
1
y”-10y’+25y=25x+35
y”-10y’+25y=25x+35
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Guest
Dec 24, 2020
0
484
1
Old question - wrong answer
Question:
A, B, C, D, and E are points on a circle of radius 2 in counterclockwise order. We know AB = BC = DE = 2 and CD = EA Find [ABCDE]. Enter your answer in the form x + y√z in the simplest radical form.
Answer:
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Guest
Dec 24, 2020
0
426
1
inequality
What values of x satisfy |x - 4| + |x + 4| <= 20?
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Guest
Dec 24, 2020
0
343
1
number theory
When working modulo m, the notation a^-1 is used to denote the residue b for which ab = 1 (mod m), if any exists. For how many integers a satisfying 0 < a < 100 is it true that a*(a - 1)^{-1} = 10a^{-1} (mod 20)?
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Guest
Dec 24, 2020
0
695
2
dinner?
Five runners together complete a 100-mile endurance race by running separate, non-overlapping portions of the course. Runner B's portion is 1.5 times the length of Runner A's portion. The combined portion for Runners C and D is twice the length of
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Guest
Dec 24, 2020
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