Question

Chứng minh 5¹+5²+5³+5⁴+5⁵+5⁶+5⁷+5⁸ chia hết cho 6 nhanh giúp mình với

Answer 1

\(5^1+5^2+5^3+...+5^8\)

\(=(5^1+5^2)+(5^3+5^4)+...+(5^7+5^8)\)

\(=5^1(1+5)+5^3(1+5)+...+5^7(1+5)\)

\(=5^1.6+5^3.6+...+5^7.6\)

\(=6(5^1+5^3+...+5^7)\)

\(\Rightarrow 5^1+5^2+5^3+...+5^8\vdots6\)

Answer 2

5^1+5^2+5^3+...+5^8

=(5^1+5^2)+(5^3+5^4)+...+(5^7+5^8)

=5^1(1+5)+5^3(1+5)+...+5^7(1+5)

=5^1.6+5^3.6+...+5^7.6

=6.(5^1+5^3+..+5^7) chia hết cho 6

Answer 3

bn ơi cho mk hay nhất