সমাধান - জ্যামিতিক ধারা

সিরিজের সাধারণ রূপ খুঁজে পেতে, প্রথম পদ: $$a=78$$ এবং সাধারণ অনুপাত: $$r=0.6538461538461539$$ জ্যামিতিক সিরিজের সূত্রে প্লাগ করুন:

$$a_1=78$$

$$a_2=a_1·r^{n-1}=78\cdot {0.6538461538461539}^{2-1}=78\cdot {0.6538461538461539}^1=78\cdot 0.6538461538461539=51$$

$$a_3=a_1·r^{n-1}=78\cdot {0.6538461538461539}^{3-1}=78\cdot {0.6538461538461539}^2=78\cdot 0.4275147928994083=33.34615384615385$$

$$a_4=a_1·r^{n-1}=78\cdot {0.6538461538461539}^{4-1}=78\cdot {0.6538461538461539}^3=78\cdot 0.27952890304961314=21.803254437869825$$

$$a_5=a_1·r^{n-1}=78\cdot {0.6538461538461539}^{5-1}=78\cdot {0.6538461538461539}^4=78\cdot 0.18276889814782396=14.255974055530269$$

$$a_6=a_1·r^{n-1}=78\cdot {0.6538461538461539}^{6-1}=78\cdot {0.6538461538461539}^5=78\cdot 0.11950274109665414=9.321213805539022$$

$$a_7=a_1·r^{n-1}=78\cdot {0.6538461538461539}^{7-1}=78\cdot {0.6538461538461539}^6=78\cdot 0.07813640764012002=6.0946397959293614$$

$$a_8=a_1·r^{n-1}=78\cdot {0.6538461538461539}^{8-1}=78\cdot {0.6538461538461539}^7=78\cdot 0.0510891896108477=3.9849567896461204$$

$$a_9=a_1·r^{n-1}=78\cdot {0.6538461538461539}^{9-1}=78\cdot {0.6538461538461539}^8=78\cdot 0.03340447013016965=2.6055486701532327$$

$$a_{10}=a_1·r^{n-1}=78\cdot {0.6538461538461539}^{10-1}=78\cdot {0.6538461538461539}^9=78\cdot 0.021841384315880157=1.7036279766386522$$