试用平方差公式计算(要详细过程,

1个回答

  • (1+1/2)*(1+1/4)*(1+1/8)*.*(1+1/2的n次方)

    =2*1/2*(1+1/2)*(1+1/4)*(1+1/8)*.*(1+1/2的n次方)

    =2*(1-1/2)(1+1/2)*(1+1/4)*(1+1/8)*.*(1+1/2的n次方)

    =2*(1-1/4)*(1+1/4)*(1+1/8)*.*(1+1/2的n次方)

    =2*(1-1/8)*(1+1/8)*.*(1+1/2的n次方)

    =2*(1-1/2的n次方)*.*(1+1/2的n次方)

    =2*(1-1/2的n+1次方)

    =2-1/2的n次方