Question

solve this tricky question please ​

Answer 1

SEE THE AATACHMENT YOUR ANSWER IS THIS AND I THINK IT IS CORRECT

#TOGETHER WE GO FAR✔✔

Answer 2

Answer:

For first term n = 1

a1 = 21 - 1

a1 = 1

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Sum of first and second term

22 - 1 = 3

1 + a2 = 3

Second term a2 = 3 - 1

a2 = 2

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Sum of first three terms

23 - 1 = 7

Third term = 7 - 3

a3 = 4

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We have first three terms a1, a2, a3

1, 2, 4..

This is a GP with first term 1 and common ratio 2

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ALITER:

We know that sum of first n terms of a GP is a[rn - 1] /(r - 1)

comparing this with 2n - 1

a = 1, r = 2