Take our quiz to find out what your revision personality is! >>

AS Level Further Maths help needed

^^
I don't need help on part a, but for part b i equaled the roots to 0 and got alpha is 1/3 and beta is 1. I then substituted in the values (b/a and c/a) and got as my answer 3x^2 +4x +1 = 0 -- is this right?

(edited 9 months ago)

Reply 1

Muttley79

Original post by lee_miller7

Can you post your working so I don't have to work right through it?

Reply 2

lee_miller7

Original post by Muttley79

Can you post your working so I don't have to work right through it?

I wrote my working above

Reply 3

Muttley79

Original post by lee_miller7

I wrote my working above

No, you said what you did - I want to see your working.

Reply 4

lee_miller7

Original post by Muttley79

No, you said what you did - I want to see your working.

It's attached

D630EAF7-266B-49E6-ABAF-F664AA83D973.jpg504.8KB

Reply 5

Muttley79

Original post by lee_miller7

It's attached

???? Roots aren't = 0

Sum of new roots =
product of new roots = then sub in from part a

Reply 6

lee_miller7

Original post by Muttley79

???? Roots aren't = 0

Sum of new roots =
product of new roots = then sub in from part a

Could you explain this a bit further please?

Reply 7

Muttley79

Original post by lee_miller7

Could you explain this a bit further please?

We can't do questions for you.

Sum of new roots = 3alpha - 1 + 3beta - 1 = 3 (alpha + beta) - 2 =

(edited 9 months ago)

Reply 8

lee_miller7

Original post by Muttley79

We can't do questions for you.

Sum of new roots = 3alpha - 1 + 3beta - 1 = 3 (alpha + beta) - 2 =

I wasn't asking you to do the question for me

Your previous reply didn't make sense to me so I asked to explain in further so I could actually understand what you were saying

Reply 9

Muttley79

Original post by lee_miller7

I wasn't asking you to do the question for me

Your previous reply didn't make sense to me so I asked to explain in further so I could actually understand what you were saying

It's a standard methosd which you shoulld have been shown - hence my surprise

Reply 10

lee_miller7

Original post by Muttley79

It's a standard methosd which you shoulld have been shown - hence my surprise

Well I haven't been shown it so could you kindly explain it perhaps??

Reply 11

mskr710

Original post by lee_miller7

Well I haven't been shown it so could you kindly explain it perhaps??

arent u supposed to do something like z*2 - (a + b)z + ab, when it says 3a - 1, the whole thing is alpha, i think u think that 3a is 3(alpha) when it is actually (3a - 1) is alpha. or maybe this isnt the way idk

(edited 9 months ago)

Reply 12

lee_miller7

is the answer 18z^2 - 24z + 11 ?

Reply 13

Muttley79

Original post by lee_miller7

Well I haven't been shown it so could you kindly explain it perhaps??

Substitute you answers to (a) into the new sum

Repeat for product

sum of new product = (3alpha -1)(3beta -1) = 9alphabeta - 3 alpha - 3 beta + 1 = 9alphabeta - 3 (alpha + beta) + 1

Again sub in answers from {a)

https://www.drfrostmaths.com/courses.php?cuid=3455