x Turn on thread page Beta
 You are Here: Home >< Maths

# solving v. simple quartics like quadratics-trig on the side watch

1. hey someone was trying to explain to me how you can solve v simple quartics by first factorising so it becomes quadratic and then just solving that. Which is great except that I cannot find the one example that he showed me

so anyway I was looking online. I'm not sure if this is the exact way the person showed ne but anyway I was trying to follow this example online. Here it is

x^4+6x^2+5

so they change it into x^2 by writing (x^2)^2+6(x^2)+5

however then they get : (x^2+5)(x^2+1)

I don't know how they have managed to get this from the step above

help would be appreciated will give rep but don't get toooo complicated with elaborate formulas as I don't need to know that
2. (Original post by CasualSoul)
hey someone was trying to explain to me how you can solve v simple quartics by first factorising so it becomes quadratic and then just solving that. Which is great except that I cannot find the one example that he showed me

so anyway I was looking online. I'm not sure if this is the exact way the person showed ne but anyway I was trying to follow this example online. Here it is

x^4+6x^2+5

so they change it into x^2 by writing (x^2)^2+6(x^2)+5

however then they get : (x^2+5)(x^2+1)

I don't know how they have managed to get this from the step above

help would be appreciated will give rep but don't get toooo complicated with elaborate formulas as I don't need to know that
Make a substitution

Now factorise

Replace u.

TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Updated: March 5, 2013
Today on TSR

### Negatives of studying at Oxbridge

What are the downsides?

Poll
Useful resources

### Maths Forum posting guidelines

Not sure where to post? Read the updated guidelines here

### How to use LaTex

Writing equations the easy way

### Study habits of A* students

Top tips from students who have already aced their exams