#Algebra

64 messages · Page 1 of 1 (latest)

lucid dust
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Hi ! Can anybody help me with this?

opal scrollBOT
wooden fulcrum
lucid dust
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its the letter ,,z"

astral hound
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could x be a geometric series?

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idk

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u could represent it as a geometric series I think...

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for 'a' part btw

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geometric sequence => u_n = u_1 * r^(n-1)

wooden fulcrum
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yeah i think its a geometric series

astral hound
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u_1 = sqrt(3)

wooden fulcrum
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do u know the forula for sum to n terms for a gp?

astral hound
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then ye

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oh wait

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we know the end term

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2020 right?

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1.3

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the formula is there

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we just need to put what is r and u1

wooden fulcrum
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yes

wooden fulcrum
astral hound
wooden fulcrum
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you can plug both of these here

astral hound
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since r < 1

wooden fulcrum
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yeah

lucid dust
astral hound
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for y it is r>1

wooden fulcrum
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i think here we can cancel out some stuff

astral hound
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r would be 3 for y

wooden fulcrum
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using the difference of squares

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identity

astral hound
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man this is the first math problem I m doing after my 12th exams

wooden fulcrum
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wait yeah we can

wooden fulcrum
astral hound
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afterall if y and x are computed then we could just put it in a calculator lol

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and then say the final result is a perfect square

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or write some proof for that

wooden fulcrum
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itll be i think ((sqrt3(1-(sqrt3)^n)/(1-sqrt3))/(3(1-3^n)/(1-3))

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you can factorise (1-3) as (1-sqrt3)(1+sqrt3)

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and (1-3^n) can be factorised as (1-(sqrt3)^n)(1+(sqrt3)^n)

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and cancel the common factors in numerator and denominator

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@lucid dust

lucid dust
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yes, wait, im processing

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guys, what grade are you ?

wooden fulcrum
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grade 10 just got done for me

lucid dust
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you just flashed in 4 seconds the whole problem

lucid dust
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i'm from a different country

wooden fulcrum
wooden fulcrum
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idk how to type latex stuff

lucid dust
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yeah, i need to translate everything on the paper and then see the steps

wooden fulcrum
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$$
\frac{\sqrt{3} \times \frac{1-\sqrt{3} n}{1-\sqrt{3}}}{3 \times \frac{1-3^n}{1-3}}
$$

tacit frigateBOT
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Renoir

wooden fulcrum
lucid dust
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you saved me

wooden fulcrum
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$$
\frac{\sqrt{3} \times \frac{1-\sqrt{3}^n}{1-\sqrt{3}}}{3 \times \frac{\left(1-\sqrt{3}^n\right)\left(1+\sqrt{3}^n\right)}{(1-\sqrt{3})(1+\sqrt{3})}}
$$

tacit frigateBOT
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Renoir

wooden fulcrum
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then cancel terms

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and then substitute