13 results.
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Question in Transition to university
Sort a list of numbers into "prime" or "composite".
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Question in Bill's workspace
Reducing fractions to their lowest form by cancelling common factors in the numerator and denominator. There are 4 questions.
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Question in Content created by Newcastle University
Solving a pair of congruences of the form x≡b1modn1x≡b2modn2 where n1,n2 are coprime.
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Question in Content created by Newcastle University
Solving two simultaneous congruences:
\begin{eqnarray*} c_1x\;&\equiv&\;b_1\;&\mod&\;n_1\\ c_2x\;&\equiv&\;b_2\;&\mod&\;n_2\\ \end{eqnarray*} where \operatorname{gcd}(c_1,n_1)=1,\;\operatorname{gcd}(c_2,n_2)=1,\;\operatorname{gcd}(n_1,n_2)=1
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Question in Content created by Newcastle University
Solving an equation of the form ax \equiv\;b\;\textrm{mod}\;n where \operatorname{gcd}(a,n)|r. In this case we can find all solutions. The user is asked for the two greatest.
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Question in Content created by Newcastle University
Solving three simultaneous congruences using the Chinese Remainder Theorem:
\begin{eqnarray*} x\;&\equiv&\;b_1\;&\mod&\;n_1\\ x\;&\equiv&\;b_2\;&\mod&\;n_2\\x\;&\equiv&\;b_3\;&\mod&\;n_3 \end{eqnarray*} where \operatorname{gcd}(n_1,n_2,n_3)=1
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Question in Content created by Newcastle University
Solving three simultaneous congruences using the Chinese Remainder Theorem:
\begin{eqnarray*} x\;&\equiv&\;b_1\;&\mod&\;n_1\\ x\;&\equiv&\;b_2\;&\mod&\;n_2\\x\;&\equiv&\;b_3\;&\mod&\;n_3 \end{eqnarray*} where \operatorname{gcd}(n_1,n_2,n_3)=1
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Question in Content created by Newcastle University
Number Theory.
Given n \in \mathbb{N} find \mu(n),\;\tau(n),\;\sigma(n),\;\phi(n).
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Question in Content created by Newcastle University
Given \frac{a}{b} \in \mathbb{Q} for suitable choices of a and b, find all n \in \mathbb{N} such that \phi(n)=\frac{a}{b}n.
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Question in Content created by Newcastle University
Given m \in \mathbb{N}, find all n \in \mathbb{N} such that \phi(n)=m and enter the largest and second largest if they exist.
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Question in Content created by Newcastle University
Factorising 5 to 7 digit numbers into a product of prime powers.
Uses the marking algorithms from question 1 of this CBA
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Question in Content created by Newcastle University
Given m \in \mathbb{N}, find values of n\in \mathbb{N} such that \sigma(n)=m.
There are at most two such solutions in this question.
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Question in Transition to university
This question tests the student's ability to identify the factors of some composite numbers and the highest common factors of two numbers.