সমাধান - জ্যামিতিক ধারা

সিরিজের সাধারণ রূপ খুঁজে পেতে, প্রথম পদ: $$a=55$$ এবং সাধারণ অনুপাত: $$r=1.8$$ জ্যামিতিক সিরিজের সূত্রে প্লাগ করুন:

$$a_1=55$$

$$a_2=a_1·r^{n-1}=55\cdot {1.8}^{2-1}=55\cdot {1.8}^1=55\cdot 1.8=99$$

$$a_3=a_1·r^{n-1}=55\cdot {1.8}^{3-1}=55\cdot {1.8}^2=55\cdot 3.24=178.20000000000002$$

$$a_4=a_1·r^{n-1}=55\cdot {1.8}^{4-1}=55\cdot {1.8}^3=55\cdot 5.832000000000001=320.76000000000005$$

$$a_5=a_1·r^{n-1}=55\cdot {1.8}^{5-1}=55\cdot {1.8}^4=55\cdot 10.4976=577.368$$

$$a_6=a_1·r^{n-1}=55\cdot {1.8}^{6-1}=55\cdot {1.8}^5=55\cdot 18.895680000000002=1039.2624$$

$$a_7=a_1·r^{n-1}=55\cdot {1.8}^{7-1}=55\cdot {1.8}^6=55\cdot 34.012224=1870.6723200000001$$

$$a_8=a_1·r^{n-1}=55\cdot {1.8}^{8-1}=55\cdot {1.8}^7=55\cdot 61.22200320000001=3367.2101760000005$$

$$a_9=a_1·r^{n-1}=55\cdot {1.8}^{9-1}=55\cdot {1.8}^8=55\cdot 110.19960576000003=6060.978316800001$$

$$a_{10}=a_1·r^{n-1}=55\cdot {1.8}^{10-1}=55\cdot {1.8}^9=55\cdot 198.35929036800005=10909.760970240002$$