Math Olympiad | A Nice Algebra Problem | VIJAY Maths
HTML-код
- Опубликовано: 8 сен 2024
- Also Watch our Most Viral Interesting Math Olympiad Problem:
• Math Olympiad | A Nice...
Subscribe to our channel and press the bell icon 🔔 for daily Brainstorming Math videos →
/ @vijaymaths5483
*****************************************************************************
#exponentialproblems #matholympiad #maths #algebra
-1
Let _uₙ = xⁿ + ⅟xⁿ_
It is easy to show that _uₙ₊₂ = uₙu₂ - uₙ₋₂_
Given that _u₁ = √3_
_u₂ = (x² + ⅟x²) = (x + ⅟x)² - 2 = u₁² - 2 = 1_
∴ _uₙ₊₂ = uₙ - uₙ₋₂_ ... ①
Since _u₀ = 2_ we can use ① to generate recursively the sequence
_u₀, u₂, u₄, u₆, u₈, u₁₀_ as
_2, 1, -1, -2, -1, 1_
after which the sequence repeats.
∴ _u₁₂ₙ₊ₓ = uₓ_ ( for even _x_ )
∴ *_u₁₀₀ = u₉₆₊₄ = u₄ = -1_*
Very good
Thanks
{x+x ➖}=x^2{ 1+1 ➖ }/{x+x ➖ }={x^2+2}/x^2= 2x^2/x^2 =2x^1 (x ➖ 2x+1) .{ x^100+x^100 ➖ }=x^200{1+1 ➖ }/{x^100+ x^100 ➖ } = {x^200+2}/x^200=2x^200/x^200= 2x^1 (x ➖ 2x+1) .