1) Chứng minh rằng :
a) 817-279+329\(⋮\)33
b) 109+108+107\(⋮\)55
c)\(\dfrac{9^{11}-9^{10}-9^9}{639}\in N\)
d)817-279-913\(⋮\)45
2) Tìm x \(\in\) N*
a)27<3x<3.81
b)415.915<2x.3x<1816.216
c)(2x-1)6=(2x-1)8
Các bạn giúp mình nha
Chứng minh rằng
a, \(7^6+7^5-7^4\) chia hết cho 55
b, \(81^7-27^9-9^{13}\) chia hết cho 405
c, \(16^5+2^{15}\) chia hết cho 33
a, B=\(\dfrac{2^{10}.13+2^{10}.65}{2^8.104}\) b, C=\(\dfrac{4^9.36+64^9}{16^4.100}\)
c, D=\(\dfrac{72^3.54^2}{108^4}\) d, E=\(\dfrac{4^6.3^4.9^5}{6^{12}}\)
chung minh rang
a, \(7^8+7^7-7^6⋮55\)
b ,\(16^5+2^{15}⋮33\)
c, \(81^7-27^9-9^{13}⋮405\)
Chứng minh rằng: a) \(2^{4^n}\)+ 4 \(⋮\) 10 ; n \(\ge\)1 ; n \(\in\) N
b) \(9^{2^n}\)+ 3 \(⋮\) 2 ; n \(\ge\) 1 ; n \(\in\) N
tính a) \(\frac{11^4.11^5}{11^4-11^5}:\frac{9^8.3-9^9}{9^8.5-9^8.7}:\frac{10^5-10^5.3}{10^5.11}\)
Chứng minh rằng
a) (8^7-2^18) chia hết cho 14
b) (81^7-27^9-9^13) chia hết cho 15
a)\(\frac{45^{10}.5^{10}}{75^{10}}\)
b)\(\frac{8^{10}+4^{10}}{8^4+4^{11}}\)
c)\(\frac{4^{20}-2^{20}+6^{20}}{6^{20}-3^{20}+9^{20}}\)
d) \(\frac{14^{16}.21^{32}.45^{48}}{10^{16}.15^{32}.7^{96}}\)
Chứng minh 810-89-88 chia hết cho 11