解答 - 几何数列

要找到系列的通用形式，将第一项：$$a=1,204$$ 和公比：$$r=0.9983388704318937$$ 插入几何级数的公式：

$$a_1=1204$$

$$a_2=a_1·r^{n-1}=1204\cdot {0.9983388704318937}^{2-1}=1204\cdot {0.9983388704318937}^1=1204\cdot 0.9983388704318937=1202$$

$$a_3=a_1·r^{n-1}=1204\cdot {0.9983388704318937}^{3-1}=1204\cdot {0.9983388704318937}^2=1204\cdot 0.9966805002152295=1200.0033222591362$$

$$a_4=a_1·r^{n-1}=1204\cdot {0.9983388704318937}^{4-1}=1204\cdot {0.9983388704318937}^3=1204\cdot 0.9950248847663671=1198.009961258706$$

$$a_5=a_1·r^{n-1}=1204\cdot {0.9983388704318937}^{5-1}=1204\cdot {0.9983388704318937}^4=1204\cdot 0.9933720195092801=1196.0199114891732$$

$$a_6=a_1·r^{n-1}=1204\cdot {0.9983388704318937}^{6-1}=1204\cdot {0.9983388704318937}^5=1204\cdot 0.9917218998755438=1194.0331674501547$$

$$a_7=a_1·r^{n-1}=1204\cdot {0.9983388704318937}^{7-1}=1204\cdot {0.9983388704318937}^6=1204\cdot 0.990074521304322=1192.0497236504038$$

$$a_8=a_1·r^{n-1}=1204\cdot {0.9983388704318937}^{8-1}=1204\cdot {0.9983388704318937}^7=1204\cdot 0.9884298792423547=1190.0695746077952$$

$$a_9=a_1·r^{n-1}=1204\cdot {0.9983388704318937}^{9-1}=1204\cdot {0.9983388704318937}^8=1204\cdot 0.9867879691439455=1188.0927148493104$$

$$a_{10}=a_1·r^{n-1}=1204\cdot {0.9983388704318937}^{10-1}=1204\cdot {0.9983388704318937}^9=1204\cdot 0.9851487864709491=1186.1191389110227$$