If 7 divides 323232 then the remainder is
We have 32 = 25
∴ (32)32=(25)32=2160(32)32=(3−1)160=160C0 3160−160C1 3159+⋯−160C1593+160C160I=3(3159−160C13158+⋯−160C159)+I=3m+1, mϵ I+Now, 323232=323m+1=25(3m+1)=215m+5
∴ 323232=23(5m+1).22=4.(8)5m+1=4.(7+1)5m+1=4.(5m+1C0(7)5m+1+5m+1C1(7)5m+5m+1C2(7)5m−1+⋯+5m+1C5m7+5m+1C5m+1)
=4[7{5m+1C075m}+5m+1C175m−1+5m+1C275m−2+⋯+5m+1C5m+1]=4[7n+1], nϵI+
= 28n + 4
This show that when 323232 is divided by 7, then the remainder is 4.