f(x)=x^4-16 hint:2i is a root
2006-12-10 13:29:14 · 8 answers · asked by Ladeanna 4 in Science & Mathematics ➔ Mathematics
That was how the question was stated.
2006-12-10 13:32:59 · update #1
You want to solve x^4 - 16 = 0.
To do this first factor the expression:
(x^2+4)(x^2-4)
And factor again:
(x^2+4)(x-2)(x+2) = 0
If a product is zero, so must be one of the factors. So set x-2 = 0 and get x = 2. Set x+2 = 0 and get x=-2. To get the remaining factors, solve the equation
x^2+4 = 0
x^2 = -4
The square roots of -4 are 2i and -2i. So the roots are 2, -2, 2i, and -2i.
2006-12-10 13:35:04 · answer #1 · answered by alnitaka 4 · 0⤊ 0⤋
break down x^4 - 16 into (x^2+4) x (x^2 - 4) then breaking down further with the quad form. gives x=+-2i, 2, -2
2006-12-10 21:35:35 · answer #2 · answered by mbarry 1 · 0⤊ 0⤋
Are you trying to find the roots? Move 16 over so that it becomes:
16=x^4
Then take the fourth root of either side.
2006-12-10 21:33:00 · answer #3 · answered by Anonymous · 0⤊ 0⤋
1. set equal to 0
2. add 16 to the other side
3. fourth root both sides
4. x equals + or - 2
2006-12-10 21:33:11 · answer #4 · answered by Olivia 1 · 0⤊ 0⤋
(x^2 - 4i)(x^2 + 4i)
(x + 2i)(x - 2i)(x^2 + 4i)
Hopefully that should help :D
2006-12-10 21:39:34 · answer #5 · answered by Anonymous · 0⤊ 0⤋
you need to give more info do this and ill help
2006-12-10 21:31:44 · answer #6 · answered by aleiva_ musica! 2 · 0⤊ 0⤋
Uhh, what do you wanna do with that equation?
2006-12-10 21:31:56 · answer #7 · answered by Noah 2 · 0⤊ 0⤋
huh? i'm 11 years old.
2006-12-10 21:33:36 · answer #8 · answered by mar.™ 3 · 0⤊ 0⤋