hoho111 hoho111
  • 02-11-2018
  • Mathematics
contestada

what are the solutions of the equation x^6-9x^3+8= 0 use u substitution to solve

Respuesta :

tramserran
tramserran tramserran
  • 02-11-2018

Answer: x = {1, 2}

Step-by-step explanation:

x⁶ - 9x³ + 8 = 0

Let u = x³  

⇒ (x³)² - 9(x³)¹ + 8(x³)⁰ = 0

⇒ u² - 9u + 8 = 0

⇒ (u - 1)(u - 8) = 0

⇒ u = 1 or u = 8

Replace u with x³

x³ = 1     or   x³ = 8

Take the cubed root of each side

x = 1     or     x = 2

 

Answer Link

Otras preguntas

Israel defeated Egypt, Jordan, and Syria in _____. World War I the Thirty Years' War World War II the Six Days War
President Monroe's foreign policy could best be described as
The technology that identifies people through bodily characteristics is known as
What's the remainder of 1/5 of 50%
Another term for basal metabolic rate is ________.
When you catch a cold, it is most likely you contracted it from _____. a. a pathogen b. rickettsia c. fleas d. mites
Determina la suma de las siguientes progresiones los primeros 18 términos de la progresión aritmética: an = -{4, 12, 20, 28, 36,,...}
How do you work out 4/5 of 65
What is the equation for the line that passes through points (4, –1) and (–4, 3)? a. b. c. d.
What's the simplified form of 2x + 3 - x + 5? a. 3x + 8 b. x - 8 c. x - 2 d. x + 8