সমাধান - জ্যামিতিক ধারা

সিরিজের সাধারণ রূপ খুঁজে পেতে, প্রথম পদ: $$a=69$$ এবং সাধারণ অনুপাত: $$r=1.2608695652173914$$ জ্যামিতিক সিরিজের সূত্রে প্লাগ করুন:

$$a_1=69$$

$$a_2=a_1·r^{n-1}=69\cdot {1.2608695652173914}^{2-1}=69\cdot {1.2608695652173914}^1=69\cdot 1.2608695652173914=87$$

$$a_3=a_1·r^{n-1}=69\cdot {1.2608695652173914}^{3-1}=69\cdot {1.2608695652173914}^2=69\cdot 1.5897920604914935=109.69565217391305$$

$$a_4=a_1·r^{n-1}=69\cdot {1.2608695652173914}^{4-1}=69\cdot {1.2608695652173914}^3=69\cdot 2.00452042409797=138.3119092627599$$

$$a_5=a_1·r^{n-1}=69\cdot {1.2608695652173914}^{5-1}=69\cdot {1.2608695652173914}^4=69\cdot 2.5274387956017885=174.39327689652342$$

$$a_6=a_1·r^{n-1}=69\cdot {1.2608695652173914}^{6-1}=69\cdot {1.2608695652173914}^5=69\cdot 3.1867706553239943=219.8871752173556$$

$$a_7=a_1·r^{n-1}=69\cdot {1.2608695652173914}^{7-1}=69\cdot {1.2608695652173914}^6=69\cdot 4.018102130625906=277.2490470131875$$

$$a_8=a_1·r^{n-1}=69\cdot {1.2608695652173914}^{8-1}=69\cdot {1.2608695652173914}^7=69\cdot 5.06630268644136=349.57488536445385$$

$$a_9=a_1·r^{n-1}=69\cdot {1.2608695652173914}^{9-1}=69\cdot {1.2608695652173914}^8=69\cdot 6.38794686551302=440.76833372039835$$

$$a_{10}=a_1·r^{n-1}=69\cdot {1.2608695652173914}^{10-1}=69\cdot {1.2608695652173914}^9=69\cdot 8.054367786951198=555.7513772996327$$