化简:2^4n+1-(4^2n+16^n)

化简：1/(n+1)(n+2)+1/(n+2)(n+3)+1/(n+3)(n+4) 化简:2^4n+1-(4^2n+16^n) 根号【（2n+1）/（n²+n）】平方-4/（n平方+n ）化简 Sn=n(n+2)(n+4)的分项等于1/6[n(n+2)(n+4)(n+5)-(n-1)n(n+2)(n+4)]吗? (n+1)(n+2)/1 +(n+2)(n+3)/1 +(n+3)(n+4)/1 [3n(n+1)+n(n+1)(2n+1)]/6+n(n+2)化简 证明：1+2C(n,1)+4C(n,2)+...+2^nC(n,n)=3^n .(n∈N+) 化简(n+1)(n+2)(n+3) 2^n/n*(n+1) (n十1)(n十2)(n十3)(n十4)十1化简 用数学归纳法证明：1×2×3+2×3×4+…+n×(n+1)×(n+2)＝n(n+1)(n+2)(n+3)4(n∈N 若n为正整数,求1/n(n+1)+1/(n+1)(n+2)＋1/(n+2)(n+3)+1/(n+3)(n+4)+.+1/