(4^n-1)/(4-1)+(1-1/4^n)/(1-1/4)+2n怎么化简?
问题描述:
(4^n-1)/(4-1)+(1-1/4^n)/(1-1/4)+2n怎么化简?
答
(2^n+1)(2^n-1)/3+4[1+(1/2^n)][1-(1/2^n)]/3+2n={(2^n+1)(2^n-1)+4[1+(1/2^n)][1-(1/2^n)]+6n}/3