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Help me factorise this! Looks simple but it's not!

16x4−10x2+1=0 16x^4 - 10x^2 +1 =0

I really need help factorising this as I have only just realised that I have never learnt how it's done. I can only factorise quadratics at this point!

Thank you for any help, I really do appreciate it and need this for a few questions.

Feel free to give me examples of different questions and their working. I'm not asking for someone to do my homework for me, I just need to understand this for a question (FP3 June 2006 Qn 3 part b) as the mark scheme if very unclear and skips working.

THANK YOU FOR THE HELP <3 <3 <3

(edited 9 years ago)
Reply 1
Avatar for MedAppli
MedAppli
1
(8x^2-1)(2x^2-1)

Posted from TSR Mobile
(edited 9 years ago)
Original post by newguy101
16x4−10x2+1=0 16x^4 - 10x^2 +1 =0

You mention you only know how to factorise quadratics but you kind of have one you can use...
A ''dummy variable'' immediately comes to mind.
Hint- let y=x^2 (this will help factor it)
np :smile:
(edited 9 years ago)
Original post by MedAppli
(8x^2-1)(2x^2-1)

Posted from TSR Mobile


It's against the TSR rules to just post the answer to the question...
Find two numbers which will multiply to give 16 and add to give 10.
Then, two numbers that multiply to give 1. A bit of help: - * - = +.
1 is a prime number.

The rest I'll give you help on later, those are just the numbers, how to find out how to factorise it is another thing, a clue is like terms.
Original post by Chittesh14
Find two numbers which will multiply to give 16 and add to give 10.
Then, two numbers that multiply to give 1. A bit of help: - * - = +.
1 is a prime number.
The rest I'll give you help on later, those are just the numbers, how to find out how to factorise it is another thing, a clue is like terms.

This method gets rather intuitive after time so you'll be able to do this without thinking too much about it. :smile:
Original post by newguy101
16x4−10x2+1=0 16x^4 - 10x^2 +1 =0

I really need help factorising this as I have only just realised that I have never learnt how it's done. I can only factorise quadratics at this point!

Thank you for any help, I really do appreciate it and need this for a few questions.

Feel free to give me examples of different questions and their working. I'm not asking for someone to do my homework for me, I just need to understand this for a question (FP3 June 2006 Qn 3 part b) as the mark scheme if very unclear and skips working.


As Mathmeister say, if you temporarily let u=x2u=x^2, then you have 16u2−10u+1=016u^2-10u+1=0, which you should be able to factorise. You can then put x^2 back in at the end.
Reply 7
Avatar for newguy101
newguy101
OP
8
Thanks so much for the help guys
Original post by newguy101
Thanks so much for the help guys


Not a problem buddy :smile:.
Reply 9
Avatar for davros
davros
16
Original post by Chittesh14
Find two numbers which will multiply to give 16 and add to give 10.
Then, two numbers that multiply to give 1. A bit of help: - * - = +.
1 is a prime number.
The rest I'll give you help on later, those are just the numbers, how to find out how to factorise it is another thing, a clue is like terms.


Your method is fine but this is not :smile:
Original post by davros
Your method is fine but this is not :smile:

Can confirm.
Original post by davros
Your method is fine but this is not :smile:


Thanks, perfect eyes! I forgot the first prime number is 2 hehe.


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