Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
1.
a) \(3^4\times3^5\times3^6=3^{4+5+6}=3^{15}\)
b) \(5^2\times5^4\times5^5\times25=5^2\times5^4\times5^5\times5^2=5^{2+4+5+2}=5^{13}\)
c) \(10^8\div10^3=10^{8-3}=10^5\)
d) \(a^7\div a^2=a^{7-2}=a^5\)
2.
\(987=900+80+7\\ =9\times100+8\times10+7\\ =9\times10^2+8\times10^1+7\times10^0\)
\(2021=2000+20+1\\ =2\times1000+2\times10+1\times1\\ =2\times10^3+2\times10^1+1\times10^0\)
\(abcde=a\times10000+b\times1000+c\times100+d\times10+e\times1\\ =a\times10^4+b\times10^3+c\times10^2+d\times10^1+e\times10^0\)
`a, 9^8 : 9^3 : 3^4`
`= 9^8 : 9^3 : 9^2`
`= 9^(8-3-2)= 9^3`.
`b, x . 4x . 16x . 64x`
`= x. 4x . 4^2x . 4^3x`
`= 4^6x^4`
\(a,3^7.27^5.81^3\\ =3^7.\left(3^3\right)^5.\left(3^4\right)^3\\ =3^7.3^{15}.3^{12}\\ =3^{34}\\ b,100^6.1000^5.10000^4\\ =100^6.100^{10}.100^{12}\\ =100^{28}\\ c,125^4:5^8\\ =5^{12}:5^8\\ =5^4.\)
\(3^8\cdot2^7\)
\(=3^7\cdot2^7\cdot3\)
\(=\left(3\cdot2\right)^7\cdot3=6^7\cdot3\)
\(=839808\)
\(3^8\times2^7=3^7\times3\times2^7=\left(3\times2\right)^7\times3=6^7\times3\)