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22 votes
22 votes
Answer:

Step by step explanation:​

Answer: Step by step explanation:​-example-1
User S Kranthi Kumar
by
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1 Answer

24 votes
24 votes

Answer:

Explanation:

a)
t_(n) = 2n - 3


t_(1)=2*1-3 = 2-3=-1\\\\t_(2)=2*2-3=4-3=1\\\\t_(3)=2*3-3=6-3=3\\\\t_(4)=2*4-3=8-3=5\\\\S_(4)=t_(1)+t_(2)+t_(3)+t_(4)\\\\= -1 + 1 + 3 + 5 \\\\= 8

d)


t_(n)=(2n-1)/(2n+1)\\\\\\t_(1)=(2-1)/(2+1)=(1)/(3)\\\\t_(2)=(4-1)/(4+1)=(3)/(5)\\\\t_(3)=(6-1)/(6+1)=(5)/(7)\\\\t_(4)=(8-1)/(8+1)=(7)/(9)\\\\


S_(n)=(n)/(2)(a+l)\\\\S_(4)=(4)/(2)((1)/(3)+(7)/(9))\\\\=2*((1*3)/(3*3)+(7)/(9))\\\\=2*((3)/(9)+(7)/(9))\\\\=2*(10)/(9)\\\\=(20)/(9)

User Sehugg
by
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