Đáp án+Giải thích các bước giải:
1) $5^15:5^5=5^{15-5}=5^{10}$
2) $9^8.3^2=3^{2.8}.3^2=3^{16}.3^2=3^{16+2}=3^{18}$
3) $7^6:49^2=7^6:7^{2.2}=7^6:7^4=7^{6-4}=7^2$
4) $25^4:5^2=5^{2.4}:5^2=5^8:5^2=5^{8-2}=5^6$
5) $2^5.8:64=2^5.2^3:2^6=2^{5+3-6}=2^2$
6) $125^7:25^10=5^{3.7}:5^{2.10}=5^21:5^20=5$
7) $120^3:40^3=(120:40)^3=3^3=27$
8) $6^56:2^28=2^{56}.3^{56}:2^{56}=2^{56-56}.3^56=1.3^56=3^{56}$