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Mikasa

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There is a problem on this take-home make up test for math for learning purpose.

 

"Find the 24th term of the expansion of (2h - k)^26 using the binomial theorem"

 

I've already found the answer via an online calculator, but I don't understand how to find this, and the teacher never taught us how to do these with a coefficient in the problem. tongue.png

 

Edit:

This is the answer

 

sNDAfkc.png

 

So the 24th term would be 239200h^4k^22, correct?

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You looking for just a answer with working for the 24th term or would you just like a method to do it and you figure it yourself?

 

I found the answer online.

This problem was on a test that I was supposed to do in class, so I have no idea how I'm supposed to come up with an answer through just doing work on paper / calculator to get to the right answer.

I put in the answer in the OP

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I found the answer online.

This problem was on a test that I was supposed to do in class, so I have no idea how I'm supposed to come up with an answer through just doing work on paper / calculator to get to the right answer.

Alright so basically to find any term in the sequence we can use this formula:

nCr.a^n-r.b^r

Where n = power index

a = first variable in bracket i.e. 2h

b = second variable including sign i.e. -k

. = Multiply coefficients

r = term your trying to find

The nCr button is on your calculator, let me know if you need further explanation I'll hop into chat.

Edited by Divinity
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okay. what you want to do to find the 24th term is

 

(NCR) x a^n-r x b^r

 

 

 

the C stands for C, if you've done statistics it'll be on your calc.

 

 n where n is 26 in this case

 

a would be 2h

 

r is 24

 

 

that = 1300 on my calculator so i am right smile.png


FFS SOMEONE ALWAYS POSTS LIKE A SECOND BEFORE ME...

 

 

edit: the 24th term would be 26C24 x 2^2 x 1^26

Edited by Aza
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Alright so basically to find any term in the sequence we can use this formula:

nCr.a^n-r.b^r

Where n = power index

a = first variable in bracket i.e. 2h

b = second variable including sign i.e. -k

. = Multiply coefficients

r = term your trying to find

The nCr button is on your calculator, let me know if you need further explanation I'll hop into chat.

 

 

okay. what you want to do to find the 24th term is

 

(NCR) x a^n-r x b^r

 

 

 

the C stands for C, if you've done statistics it'll be on your calc.

 

 n where n is 26 in this case

 

a would be 2h

 

r is 24

 

 

that = 1300 on my calculator so i am right smile.png

FFS SOMEONE ALWAYS POSTS LIKE A SECOND BEFORE ME...

 

 

edit: the 24th term would be 26C24 x 2^2 x 1^26

 

My brain just exploded.

I have a basic bitch calculator, so I don't have that button :p

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Dayum that sucks, the long way is such a killer. Do you not have a scientific calculator?

 

This is what I have, which I am borrowing from the library - http://education.ti.com/en/us/products/calculators/scientific-calculators/ti-30x-iis/tabs/overview

 

I should probably invest in a good calculator, since what I want to major in requires a lot of math classes ._.

My teacher just kind of sucks and never taught us how to go this far into the expansion, especially if there is a coefficient, so I'm lost.

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This is what I have, which I am borrowing from the library - http://education.ti.com/en/us/products/calculators/scientific-calculators/ti-30x-iis/tabs/overview

I should probably invest in a good calculator, since what I want to major in requires a lot of math classes ._.

My teacher just kind of sucks and never taught us how to go this far into the expansion, especially if there is a coefficient, so I'm lost.

That will do, you see the "PRB" button? One button underneath it, A/Something press it and you should get the nCr option ^_^

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A scientific calculator will cost like £10.

I've had mine for 6 years now, hasn't run out of battery and does everything i need it to. Casio Natural Display FX-83ES 

 

Unless you find drawing graphs and such hard spend £50/60 on a graphics calculator and it'll literally be your bitch, just make sure you can take it into exams.

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That will do, you see the "PRB" button? One button underneath it, A/Something press it and you should get the nCr option happy.png

 

I clicked it & it gave me this symbol

 

GBcd8h8.png

 

& as you said, a = first variable in bracket i.e. 2h, so I'd input the h as well? can't seem to figure out how to do variables on this calculator.

It's 3 am, I feel like dying at this point

A scientific calculator will cost like £10.

I've had mine for 6 years now, hasn't run out of battery and does everything i need it to. Casio Natural Display FX-83ES 

 

Unless you find drawing graphs and such hard spend £50/60 on a graphics calculator and it'll literally be your bitch, just make sure you can take it into exams.

 

Yeah, I want to get a graphing one, I suck dick at graphing.

My current problem I'm working on is "Graph the following equation and using that graph tell which is true: x^2 + y^2 - 2x + 6y = 6"

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