Question

hey !!


please answer (ii) .

thankeww

Answer 1

Heya!!

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=) Sn = n/2 [2a +(n-1)d]

Here n= 19
a= 3/4
d = 2/3 - 3/4

= - 1/12

Hence S19 = 19/2 [2(3/4) + (19-1)(-1/12)]

= 19/2 [3/2 - 18/12)

= 19/2 (0)

= 0

Hope it helps uh!!

Answer 2

Heya!
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♦Sequence and Series ♦
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➡Given Series =>
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◾3/4 + 2/3 + 7/12................ 19 terms .


Here ,
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◾First term a = 3/4

◾Common Difference d = -1/12

◾No. Of terms n = 19


Using the formula for Sn=>
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=> Sn = n/2 [ 2a + ( n - 1 ) d ]

=> Sn = 19/2 [ 2 × 3/4 + ( 18 ) -1/12 ]

=> Sn = 19/2 [ 3/2 -3/2 ]

=> Sn = 19/2 × 0


=> Sn = 0


✴Hence the Sum up to 19 terms is 0


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