Maths Olympiad Prep

Library / /98 of 520

Number theory Difficulty 5.6 AIME, harder Find the answer

2. 求下列模为素数幂的同余方程的解:
(i) x3+x2+10x+10(mod33)x^{3}+x^{2}+10 x+1 \equiv 0\left(\bmod 3^{3}\right);
(ii) x3+25x+30(mod33)x^{3}+25 x+3 \equiv 0\left(\bmod 3^{3}\right);
(iii) x35x2+30(mod34)x^{3}-5 x^{2}+3 \equiv 0\left(\bmod 3^{4}\right);
(iv) x5+x4+10(mod34)x^{5}+x^{4}+1 \equiv 0\left(\bmod 3^{4}\right);
(v) x32x+40(mod53)x^{3}-2 x+4 \equiv 0\left(\bmod 5^{3}\right);
(vi) x3+x+570(mod53)x^{3}+x+57 \equiv 0\left(\bmod 5^{3}\right);
(vii) x3+x240(mod73)x^{3}+x^{2}-4 \equiv 0\left(\bmod 7^{3}\right);
(viii) x3+x250(mod73)x^{3}+x^{2}-5 \equiv 0\left(\bmod 7^{3}\right);
(ix) x2+5x+130(mod33)x^{2}+5 x+13 \equiv 0\left(\bmod 3^{3}\right);
(x) x2+5x+130(mod34)x^{2}+5 x+13 \equiv 0\left(\bmod 3^{4}\right);
(xi) x23(mod113)x^{2} \equiv 3\left(\bmod 11^{3}\right);
(xii) x22(mod194)x^{2} \equiv-2\left(\bmod 19^{4}\right).

A number or a short expression. Spacing and $ signs are ignored.

Solution

2. (i) x10(mod33)x \equiv-10\left(\bmod 3^{3}\right);
(ii) x12(mod33)x \equiv-12\left(\bmod 3^{3}\right);
(iii) x11(mod34)x \equiv 11\left(\bmod 3^{4}\right);
(iv) 无解;
(v) x56,2+25j,8+25j(modx \equiv-56,-2+25 \cdot j, 8+25 j(\bmod
53),j=0,±1,±2\left.5^{3}\right), j=0, \pm 1, \pm 2;
(vi) x4(mod53)x \equiv 4\left(\bmod 5^{3}\right);
(vii) 无解;
(viii) x23(mod73)x \equiv 23\left(\bmod 7^{3}\right);
(ix) x2+9j(mod33),j=0,±1x \equiv 2+9 j\left(\bmod 3^{3}\right), j=0, \pm 1
(x) 无解;
(xi) x±578(mod113)x \equiv \pm 578\left(\bmod 11^{3}\right);
(xii) x±(2590+4193)±30026(mod194)x \equiv \pm\left(2590+4 \cdot 19^{3}\right) \equiv \pm 30026\left(\bmod 19^{4}\right).

Want a route through all this instead of an archive? The track puts 2,000 problems in a working order, from AMC 10 level to the IMO shortlist.

Source: NuminaMath-1.5, licensed Apache-2.0. Statement and solution reproduced as published; topic and difficulty added by this site.