A question related to Number Theory

I am a beginner with Number theory and I came across a problem which I could not solve

Remainder when $2^{1990}$ is divided by $1990$ ??

Please state the theorem used in this as well as the algorithm.

#NumberTheory #CosinesGroup #Goldbach'sConjurersGroup #Ilovenumbertheory

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Math	Appears as
Remember to wrap math in `$` ... `$` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$

Comments

http://answers.yahoo.com/question/index?qid=20080829233721AAo0yuM http://in.answers.yahoo.com/question/index?qid=20110627032530AAc2u8l Check these links out...probably they might help you....

Tanya Gupta - 7 years, 3 months ago

Ya these were probably helpful! But its difficult to digest all such material.

Thanks for helping!

Pankaj Joshi - 7 years, 3 months ago

You r most welcome!!

Tanya Gupta - 7 years, 3 months ago

Fermat's Little Theorem

Agnishom Chattopadhyay - 7 years, 3 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$