Question

mathematic induction

Answer 1

a)first:1*2=1/3*1*2*3=22nd:if 1*2+2*3+3*4+.+n(n+1)=1/3*n(n+1)(n+2) then:1*2+2*3+3*4+.+n(n+1)+(n+1)(n+2)=1/3*n(n+1)(n+2)+(n+1)(n+2)=(n+1)(n+2)(n/3+1)=1/3(n+1)(n+2)(n+3)so:1*2+2*3+3*4+.+n(n+1)=1/3*n(n+1...