Math Is Fun Forum
Discussion about math, puzzles, games and fun. Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ π -¹ ² ³ °
You are not logged in.
- Topics: Active | Unanswered
#1 2018-07-14 19:44:20
- Zeeshan 01
- Member
- Registered: 2016-07-22
- Posts: 746
Quadratic
Question: If (3x^2)-2x+4=0 , Then Find α^19 , beta^-3
Malik
Offline
#2 2018-07-15 00:12:13
- Alg Num Theory
- Member
- Registered: 2017-11-24
- Posts: 693
- Website
Re: Quadratic
I presume ɑ and β are the roots, which are complex. Since we are going to deal with their powers, best to convert them to cos–sin form:
[list=*]
[*]
[/list]
So the roots are
[list=*]
[*]
[/list]
one of them is ɑ, the other is β. Since the question doesn’t say which is which, you may as well take your pick. Now use De Moivre’s theorem.
Last edited by Alg Num Theory (2018-07-15 07:08:15)
Me, or the ugly man, whatever (3,3,6)
Offline