Question

Hello friends,

plss answer this
and previous two also

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Answer 1

Answer:

$b) \dfrac{7}{81} (179 + {10}^{ - 20} )$

Step-by-step explanation:

Solution---->

1) please refer the attachment

2) sum of n terms of gp is

sₙ = a ( 1 - rⁿ ) / ( 1 - r )

3) if we add 1 twenty times we get 20 times

Additional information

1) nth term of gp is

aₙ = a rⁿ⁻¹

Where a = first term

r = common ratio

= a₂/ a₁

2) sum of infinite terms of gp

s ( infinite terms) = a / ( 1 - r )

3) nth term of ap

aₙ = a + ( n - 1 ) d

4) sum of n terms of ap

sₙ = n/2 { 2a + ( n - 1 ) d }

Answer 2

Answer:

Hello sis where r u .....