Quick Series and Sequences question? (1 Viewer)

Zokunu

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Littlehelp with question 1 and 10A ?

StepbyStep or any working out would be nice. TY :)
 

HeroicPandas

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Tn represents the nth term of this sequence

So the first (1th) term is T1
So the second (2th) term is T2
So the third (3th) term is T3

Therefore let n = 1, 2, 3 to find the first, second and third term respectively
 

braintic

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Q10a

a + (a+d) = 10

(a+4d) + (a+7d) = 51

Solve simultaneously for a and d.

Then use these values to evaluate a + (a+7d).
 

think

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For 10 a I got 34.6, working is attached but it is messy.
Basically you need to get two simultaneous equations using Tn and Sn formula for an AP. Then find a and d and then solve for T8 plus T1 or a.
001.jpg
Edit: same as above
 

Carrotsticks

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I am curious, from where did you acquire such a worksheet?

It looks like it's been made in TeX, and few schools do that...
 

Zokunu

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I am curious, from where did you acquire such a worksheet?

It looks like it's been made in TeX, and few schools do that...
TY all :). And carrot I got the sheet that from my tutor "Focus College".

I got another question related to SAS. Littlehelp?

The numbers 3,x,y are in arithmetic progression and x,y,25 are in geometric progression. Find x and y. TY.
 

braintic

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TY all :). And carrot I got the sheet that from my tutor "Focus College".

I got another question related to SAS. Littlehelp?

The numbers 3,x,y are in arithmetic progression and x,y,25 are in geometric progression. Find x and y. TY.
x-3 = y-x
2x = y+3

y/x = 25/y
y^2 = 25x

Then solve simultaneously.
 

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