সমাধান - জ্যামিতিক ধারা

সিরিজের সাধারণ রূপ খুঁজে পেতে, প্রথম পদ: $$a=60$$ এবং সাধারণ অনুপাত: $$r=12.5$$ জ্যামিতিক সিরিজের সূত্রে প্লাগ করুন:

$$a_1=60$$

$$a_2=a_1·r^{n-1}=60\cdot {12.5}^{2-1}=60\cdot {12.5}^1=60\cdot 12.5=750$$

$$a_3=a_1·r^{n-1}=60\cdot {12.5}^{3-1}=60\cdot {12.5}^2=60\cdot 156.25=9375$$

$$a_4=a_1·r^{n-1}=60\cdot {12.5}^{4-1}=60\cdot {12.5}^3=60\cdot 1953.125=117187.5$$

$$a_5=a_1·r^{n-1}=60\cdot {12.5}^{5-1}=60\cdot {12.5}^4=60\cdot 24414.0625=1464843.75$$

$$a_6=a_1·r^{n-1}=60\cdot {12.5}^{6-1}=60\cdot {12.5}^5=60\cdot 305175.78125=18310546.875$$

$$a_7=a_1·r^{n-1}=60\cdot {12.5}^{7-1}=60\cdot {12.5}^6=60\cdot 3814697.265625=228881835.9375$$

$$a_8=a_1·r^{n-1}=60\cdot {12.5}^{8-1}=60\cdot {12.5}^7=60\cdot 47683715.8203125=2861022949.21875$$

$$a_9=a_1·r^{n-1}=60\cdot {12.5}^{9-1}=60\cdot {12.5}^8=60\cdot 596046447.7539062=35762786865.234375$$

$$a_{10}=a_1·r^{n-1}=60\cdot {12.5}^{10-1}=60\cdot {12.5}^9=60\cdot 7450580596.923828=447034835815.4297$$