Remainder on division with $22$
$begingroup$
What is the remainder obtained when $14^{16}$ is divided with $22$?
Is there a general method for this, without using number theory? I wish to solve this question using binomial theorem only - maybe expressing the numerator as a summation in which most terms are divisible by $22$, except the remainder?
How should I proceed?
number-theory elementary-number-theory modular-arithmetic divisibility binomial-theorem
$endgroup$
add a comment |
$begingroup$
What is the remainder obtained when $14^{16}$ is divided with $22$?
Is there a general method for this, without using number theory? I wish to solve this question using binomial theorem only - maybe expressing the numerator as a summation in which most terms are divisible by $22$, except the remainder?
How should I proceed?
number-theory elementary-number-theory modular-arithmetic divisibility binomial-theorem
$endgroup$
$begingroup$
$14^{16} = (22 - 8)^{16}$
$endgroup$
– ab123
Jul 3 '18 at 10:37
$begingroup$
$8^{16} = 64^8 = (66 - 2)^8$
$endgroup$
– ab123
Jul 3 '18 at 10:41
7
$begingroup$
@ab123 Why not make an answer of that?
$endgroup$
– Arthur
Jul 3 '18 at 10:41
add a comment |
$begingroup$
What is the remainder obtained when $14^{16}$ is divided with $22$?
Is there a general method for this, without using number theory? I wish to solve this question using binomial theorem only - maybe expressing the numerator as a summation in which most terms are divisible by $22$, except the remainder?
How should I proceed?
number-theory elementary-number-theory modular-arithmetic divisibility binomial-theorem
$endgroup$
What is the remainder obtained when $14^{16}$ is divided with $22$?
Is there a general method for this, without using number theory? I wish to solve this question using binomial theorem only - maybe expressing the numerator as a summation in which most terms are divisible by $22$, except the remainder?
How should I proceed?
number-theory elementary-number-theory modular-arithmetic divisibility binomial-theorem
number-theory elementary-number-theory modular-arithmetic divisibility binomial-theorem
edited Jan 12 at 6:10
Abcd
3,02821235
3,02821235
asked Jul 3 '18 at 10:32
arya_starkarya_stark
676218
676218
$begingroup$
$14^{16} = (22 - 8)^{16}$
$endgroup$
– ab123
Jul 3 '18 at 10:37
$begingroup$
$8^{16} = 64^8 = (66 - 2)^8$
$endgroup$
– ab123
Jul 3 '18 at 10:41
7
$begingroup$
@ab123 Why not make an answer of that?
$endgroup$
– Arthur
Jul 3 '18 at 10:41
add a comment |
$begingroup$
$14^{16} = (22 - 8)^{16}$
$endgroup$
– ab123
Jul 3 '18 at 10:37
$begingroup$
$8^{16} = 64^8 = (66 - 2)^8$
$endgroup$
– ab123
Jul 3 '18 at 10:41
7
$begingroup$
@ab123 Why not make an answer of that?
$endgroup$
– Arthur
Jul 3 '18 at 10:41
$begingroup$
$14^{16} = (22 - 8)^{16}$
$endgroup$
– ab123
Jul 3 '18 at 10:37
$begingroup$
$14^{16} = (22 - 8)^{16}$
$endgroup$
– ab123
Jul 3 '18 at 10:37
$begingroup$
$8^{16} = 64^8 = (66 - 2)^8$
$endgroup$
– ab123
Jul 3 '18 at 10:41
$begingroup$
$8^{16} = 64^8 = (66 - 2)^8$
$endgroup$
– ab123
Jul 3 '18 at 10:41
7
7
$begingroup$
@ab123 Why not make an answer of that?
$endgroup$
– Arthur
Jul 3 '18 at 10:41
$begingroup$
@ab123 Why not make an answer of that?
$endgroup$
– Arthur
Jul 3 '18 at 10:41
add a comment |
4 Answers
4
active
oldest
votes
$begingroup$
You can use binomial expansions and see that
$$14^{16} = (22 - 8)^{16}$$
implies that the remainder is just the remainder when $(-8)^{16}( = 8^{16})$ is divided by $22.$
Proceeding similarly,
$8^{16} = 64^8 = (66 - 2)^8 implies 2^8 = 256 text{ divided by } 22 implies text{remainder = 14}$
$endgroup$
add a comment |
$begingroup$
Since $$ 14^2 equiv -2 $$ so $$14^{16} equiv (-2)^8 equiv 16^2equiv (-6)^2 equiv 14$$
or
$$ 14^2 = 22k -2 $$ so $$14^{16} = (22k-2)^8 = 22l+2^8=22l+22cdot 11+14$$
$endgroup$
add a comment |
$begingroup$
A method that uses FLT.
Finding the remainder on dividing $14^{16}$ by $22$ is equivalent to twice that on dividing $7cdot14^{15}$ by $11$.
By FLT, $14^{10}equiv1pmod{11}$ so $$7cdot14^{15}equiv7cdot14^5equiv98cdot196cdot196equiv-1cdot(-2)cdot(-2)equiv-4equiv7pmod{11}$$ hence the required remainder is $7times 2=14$.
$endgroup$
add a comment |
$begingroup$
Using the Euclidean Algorithm
Note that
$$
begin{align}
14^{16}&equiv0&pmod2tag1
end{align}
$$
Reducing mod $11$ and using Fermat's Little Theorem, we get
$$
begin{align}
14^{16}
&equiv3^6&pmod{11}\
&equiv3&pmod{11}tag2
end{align}
$$
Solving $11a+2b=1$ using the Euclidean Algorithm as implemented in this answer,
$$
begin{array}{r}
&&5&2\hline
1&0&1&-2\
0&1&-5&11\
11&2&1&0\
end{array}tag3
$$
we have
$$
11(1)+2(-5)=1tag4
$$
from which we get
$$
begin{align}
-10&equiv0&pmod2\
-10&equiv1&pmod{11}
end{align}tag5
$$
Multiplying $(5)$ by $3$ gives
$$
begin{align}
-30&equiv0&pmod2\
-30&equiv3&pmod{11}
end{align}tag6
$$
Using the Chinese Remainder Theorem
The Chinese Remainder Theorem says that the solution to $(6)$ is unique mod ${22}$. Thus, we get the smallest positive solution to be
$$
begin{align}
14&equiv0&pmod2\
14&equiv3&pmod{11}
end{align}tag7
$$
Thus, $(1)$, $(2)$, and $(7)$ yields
$$
begin{align}
14^{16}&equiv14&pmod{22}tag8
end{align}
$$
$endgroup$
add a comment |
Your Answer
StackExchange.ifUsing("editor", function () {
return StackExchange.using("mathjaxEditing", function () {
StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
});
});
}, "mathjax-editing");
StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "69"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});
function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
noCode: true, onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});
}
});
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f2839477%2fremainder-on-division-with-22%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
4 Answers
4
active
oldest
votes
4 Answers
4
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
You can use binomial expansions and see that
$$14^{16} = (22 - 8)^{16}$$
implies that the remainder is just the remainder when $(-8)^{16}( = 8^{16})$ is divided by $22.$
Proceeding similarly,
$8^{16} = 64^8 = (66 - 2)^8 implies 2^8 = 256 text{ divided by } 22 implies text{remainder = 14}$
$endgroup$
add a comment |
$begingroup$
You can use binomial expansions and see that
$$14^{16} = (22 - 8)^{16}$$
implies that the remainder is just the remainder when $(-8)^{16}( = 8^{16})$ is divided by $22.$
Proceeding similarly,
$8^{16} = 64^8 = (66 - 2)^8 implies 2^8 = 256 text{ divided by } 22 implies text{remainder = 14}$
$endgroup$
add a comment |
$begingroup$
You can use binomial expansions and see that
$$14^{16} = (22 - 8)^{16}$$
implies that the remainder is just the remainder when $(-8)^{16}( = 8^{16})$ is divided by $22.$
Proceeding similarly,
$8^{16} = 64^8 = (66 - 2)^8 implies 2^8 = 256 text{ divided by } 22 implies text{remainder = 14}$
$endgroup$
You can use binomial expansions and see that
$$14^{16} = (22 - 8)^{16}$$
implies that the remainder is just the remainder when $(-8)^{16}( = 8^{16})$ is divided by $22.$
Proceeding similarly,
$8^{16} = 64^8 = (66 - 2)^8 implies 2^8 = 256 text{ divided by } 22 implies text{remainder = 14}$
edited Jul 3 '18 at 10:48
answered Jul 3 '18 at 10:45
ab123ab123
1,654423
1,654423
add a comment |
add a comment |
$begingroup$
Since $$ 14^2 equiv -2 $$ so $$14^{16} equiv (-2)^8 equiv 16^2equiv (-6)^2 equiv 14$$
or
$$ 14^2 = 22k -2 $$ so $$14^{16} = (22k-2)^8 = 22l+2^8=22l+22cdot 11+14$$
$endgroup$
add a comment |
$begingroup$
Since $$ 14^2 equiv -2 $$ so $$14^{16} equiv (-2)^8 equiv 16^2equiv (-6)^2 equiv 14$$
or
$$ 14^2 = 22k -2 $$ so $$14^{16} = (22k-2)^8 = 22l+2^8=22l+22cdot 11+14$$
$endgroup$
add a comment |
$begingroup$
Since $$ 14^2 equiv -2 $$ so $$14^{16} equiv (-2)^8 equiv 16^2equiv (-6)^2 equiv 14$$
or
$$ 14^2 = 22k -2 $$ so $$14^{16} = (22k-2)^8 = 22l+2^8=22l+22cdot 11+14$$
$endgroup$
Since $$ 14^2 equiv -2 $$ so $$14^{16} equiv (-2)^8 equiv 16^2equiv (-6)^2 equiv 14$$
or
$$ 14^2 = 22k -2 $$ so $$14^{16} = (22k-2)^8 = 22l+2^8=22l+22cdot 11+14$$
edited Jul 3 '18 at 10:53
answered Jul 3 '18 at 10:39
greedoidgreedoid
39.9k114798
39.9k114798
add a comment |
add a comment |
$begingroup$
A method that uses FLT.
Finding the remainder on dividing $14^{16}$ by $22$ is equivalent to twice that on dividing $7cdot14^{15}$ by $11$.
By FLT, $14^{10}equiv1pmod{11}$ so $$7cdot14^{15}equiv7cdot14^5equiv98cdot196cdot196equiv-1cdot(-2)cdot(-2)equiv-4equiv7pmod{11}$$ hence the required remainder is $7times 2=14$.
$endgroup$
add a comment |
$begingroup$
A method that uses FLT.
Finding the remainder on dividing $14^{16}$ by $22$ is equivalent to twice that on dividing $7cdot14^{15}$ by $11$.
By FLT, $14^{10}equiv1pmod{11}$ so $$7cdot14^{15}equiv7cdot14^5equiv98cdot196cdot196equiv-1cdot(-2)cdot(-2)equiv-4equiv7pmod{11}$$ hence the required remainder is $7times 2=14$.
$endgroup$
add a comment |
$begingroup$
A method that uses FLT.
Finding the remainder on dividing $14^{16}$ by $22$ is equivalent to twice that on dividing $7cdot14^{15}$ by $11$.
By FLT, $14^{10}equiv1pmod{11}$ so $$7cdot14^{15}equiv7cdot14^5equiv98cdot196cdot196equiv-1cdot(-2)cdot(-2)equiv-4equiv7pmod{11}$$ hence the required remainder is $7times 2=14$.
$endgroup$
A method that uses FLT.
Finding the remainder on dividing $14^{16}$ by $22$ is equivalent to twice that on dividing $7cdot14^{15}$ by $11$.
By FLT, $14^{10}equiv1pmod{11}$ so $$7cdot14^{15}equiv7cdot14^5equiv98cdot196cdot196equiv-1cdot(-2)cdot(-2)equiv-4equiv7pmod{11}$$ hence the required remainder is $7times 2=14$.
answered Jul 3 '18 at 14:12
TheSimpliFireTheSimpliFire
12.4k62460
12.4k62460
add a comment |
add a comment |
$begingroup$
Using the Euclidean Algorithm
Note that
$$
begin{align}
14^{16}&equiv0&pmod2tag1
end{align}
$$
Reducing mod $11$ and using Fermat's Little Theorem, we get
$$
begin{align}
14^{16}
&equiv3^6&pmod{11}\
&equiv3&pmod{11}tag2
end{align}
$$
Solving $11a+2b=1$ using the Euclidean Algorithm as implemented in this answer,
$$
begin{array}{r}
&&5&2\hline
1&0&1&-2\
0&1&-5&11\
11&2&1&0\
end{array}tag3
$$
we have
$$
11(1)+2(-5)=1tag4
$$
from which we get
$$
begin{align}
-10&equiv0&pmod2\
-10&equiv1&pmod{11}
end{align}tag5
$$
Multiplying $(5)$ by $3$ gives
$$
begin{align}
-30&equiv0&pmod2\
-30&equiv3&pmod{11}
end{align}tag6
$$
Using the Chinese Remainder Theorem
The Chinese Remainder Theorem says that the solution to $(6)$ is unique mod ${22}$. Thus, we get the smallest positive solution to be
$$
begin{align}
14&equiv0&pmod2\
14&equiv3&pmod{11}
end{align}tag7
$$
Thus, $(1)$, $(2)$, and $(7)$ yields
$$
begin{align}
14^{16}&equiv14&pmod{22}tag8
end{align}
$$
$endgroup$
add a comment |
$begingroup$
Using the Euclidean Algorithm
Note that
$$
begin{align}
14^{16}&equiv0&pmod2tag1
end{align}
$$
Reducing mod $11$ and using Fermat's Little Theorem, we get
$$
begin{align}
14^{16}
&equiv3^6&pmod{11}\
&equiv3&pmod{11}tag2
end{align}
$$
Solving $11a+2b=1$ using the Euclidean Algorithm as implemented in this answer,
$$
begin{array}{r}
&&5&2\hline
1&0&1&-2\
0&1&-5&11\
11&2&1&0\
end{array}tag3
$$
we have
$$
11(1)+2(-5)=1tag4
$$
from which we get
$$
begin{align}
-10&equiv0&pmod2\
-10&equiv1&pmod{11}
end{align}tag5
$$
Multiplying $(5)$ by $3$ gives
$$
begin{align}
-30&equiv0&pmod2\
-30&equiv3&pmod{11}
end{align}tag6
$$
Using the Chinese Remainder Theorem
The Chinese Remainder Theorem says that the solution to $(6)$ is unique mod ${22}$. Thus, we get the smallest positive solution to be
$$
begin{align}
14&equiv0&pmod2\
14&equiv3&pmod{11}
end{align}tag7
$$
Thus, $(1)$, $(2)$, and $(7)$ yields
$$
begin{align}
14^{16}&equiv14&pmod{22}tag8
end{align}
$$
$endgroup$
add a comment |
$begingroup$
Using the Euclidean Algorithm
Note that
$$
begin{align}
14^{16}&equiv0&pmod2tag1
end{align}
$$
Reducing mod $11$ and using Fermat's Little Theorem, we get
$$
begin{align}
14^{16}
&equiv3^6&pmod{11}\
&equiv3&pmod{11}tag2
end{align}
$$
Solving $11a+2b=1$ using the Euclidean Algorithm as implemented in this answer,
$$
begin{array}{r}
&&5&2\hline
1&0&1&-2\
0&1&-5&11\
11&2&1&0\
end{array}tag3
$$
we have
$$
11(1)+2(-5)=1tag4
$$
from which we get
$$
begin{align}
-10&equiv0&pmod2\
-10&equiv1&pmod{11}
end{align}tag5
$$
Multiplying $(5)$ by $3$ gives
$$
begin{align}
-30&equiv0&pmod2\
-30&equiv3&pmod{11}
end{align}tag6
$$
Using the Chinese Remainder Theorem
The Chinese Remainder Theorem says that the solution to $(6)$ is unique mod ${22}$. Thus, we get the smallest positive solution to be
$$
begin{align}
14&equiv0&pmod2\
14&equiv3&pmod{11}
end{align}tag7
$$
Thus, $(1)$, $(2)$, and $(7)$ yields
$$
begin{align}
14^{16}&equiv14&pmod{22}tag8
end{align}
$$
$endgroup$
Using the Euclidean Algorithm
Note that
$$
begin{align}
14^{16}&equiv0&pmod2tag1
end{align}
$$
Reducing mod $11$ and using Fermat's Little Theorem, we get
$$
begin{align}
14^{16}
&equiv3^6&pmod{11}\
&equiv3&pmod{11}tag2
end{align}
$$
Solving $11a+2b=1$ using the Euclidean Algorithm as implemented in this answer,
$$
begin{array}{r}
&&5&2\hline
1&0&1&-2\
0&1&-5&11\
11&2&1&0\
end{array}tag3
$$
we have
$$
11(1)+2(-5)=1tag4
$$
from which we get
$$
begin{align}
-10&equiv0&pmod2\
-10&equiv1&pmod{11}
end{align}tag5
$$
Multiplying $(5)$ by $3$ gives
$$
begin{align}
-30&equiv0&pmod2\
-30&equiv3&pmod{11}
end{align}tag6
$$
Using the Chinese Remainder Theorem
The Chinese Remainder Theorem says that the solution to $(6)$ is unique mod ${22}$. Thus, we get the smallest positive solution to be
$$
begin{align}
14&equiv0&pmod2\
14&equiv3&pmod{11}
end{align}tag7
$$
Thus, $(1)$, $(2)$, and $(7)$ yields
$$
begin{align}
14^{16}&equiv14&pmod{22}tag8
end{align}
$$
answered Jul 3 '18 at 15:05
robjohn♦robjohn
266k27306629
266k27306629
add a comment |
add a comment |
Thanks for contributing an answer to Mathematics Stack Exchange!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
Use MathJax to format equations. MathJax reference.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f2839477%2fremainder-on-division-with-22%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
$begingroup$
$14^{16} = (22 - 8)^{16}$
$endgroup$
– ab123
Jul 3 '18 at 10:37
$begingroup$
$8^{16} = 64^8 = (66 - 2)^8$
$endgroup$
– ab123
Jul 3 '18 at 10:41
7
$begingroup$
@ab123 Why not make an answer of that?
$endgroup$
– Arthur
Jul 3 '18 at 10:41