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The first term of GP where second term is 2 and sum of infinity is8 it will be​

User Shonte
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1 Answer

1 vote

Answer:

a = 4

Step-by-step explanation: Given that

ar=2 where a is the first term and is the common ratio.

ar=2 ............1

Also give that a/1-r = 8 where a is the first term and r is the common ratio as well.

a/1-r = 8 ......... 2

From equation 1 make r the subject

ar=2

r= 2/a...........3

Put equation 3 into 2

a/1-2/a =8

a÷1-2/a

a = 8(1-2/a)

a= 8/1-16/a

a/1= 8a-16

a^2= 8a-16

Rewriting the above equation

a^2-8a+16=0

This will eventually be

a^2-8a+16=0

(a-4)^2= 0

a =4

User Scro
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