懂视
0.9+0.9²+0.9³……=
2024-12-04 14:55:35
等比数列的求和公式是：Sn=a1(1-q^n)/(1-q)所以,原式=1+0.9(1-0.9^9)/(1-0.9)=1+5.53215599=6.53215599
等比数列的求和公式是：Sn=a1(1-q^n)/(1-q)所以,原式=1+0.9(1-0.9^9)/(1-0.9)=1+5.53215599=6.53215599