CUET Preparation Today
If $17^{241}≡R(mod\, 13)$, then value of R is : |
1 3 4 9 |
4 |
Compute $17^{241}\pmod{13}$. $17\equiv 4 \pmod{13}$ So $17^{241}\equiv 4^{241}\pmod{13}$. Since $13$ is prime, $\phi(13)=12$. $4^{12}\equiv 1 \pmod{13}$ $241\equiv 1 \pmod{12}$ Hence $4^{241}\equiv 4^{1}\equiv 4 \pmod{13}$ final answer: $4$ |
