SOlve by Factoring:6x^4-5x^2-4=0

Question

1645323 · Answer

@phi

phi · Answer

you did not finish the other problem.

this one is complicated.

1645323 · Answer

I got the other problem

1645323 · Answer

@phi

phi · Answer

I'll type out the final answer in the other post.

phi · Answer

in this problem
$$ 6x^4-5x^2-4=0 $$
you list the 6 (from the x^4) and the -4 (last term)
6* -4 = -24
the minus means the factors are different signs
list the factors that give 24
1,24
2,12
3,8
4,6

look for a pair that add up to -5 when they have different signs (the bigger number must be negative)

1-24= -23
2 - 12 = -10
3 - 8 = -5 <---- this one works
4-6= -2

phi · Answer

the answer will be
(2x^2     ) (3 x^2      )
we need a -8 which means we want
(2x^2     )( 3x^2 - 4)
the other number must be +1 
(2x^2+1 )( 3x^2 - 4)

This is a hard problem to explain clearly.

1645323 · Answer

ok thanks