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

if a pH of water is 5.3 then 4.3 is it 1.0 less acidic 1.0 less basic
Which of the following is x⁴ + y⁴ identically equal to? (A) (x² + y²)(x + y)(x - y) (B) (x² + xy + y²)(x² - xy + y²) (C) (x² + √2xy + y²)(x² - √2xy + y²) (D) (x
Randal answers 96 out of 120 questions correctly on a science exam. What percent of the questions did Randal answer correctly
If 2x+z=2y and 2x+2y+z=20 what is the value of y?
What is does the phrase foe to ambition.
Simple Machine Lever: A ________ that pivots on top of a fixed point called a _______.
which of the following organisms feeds on the largest variety of producers
THE EXPRESSION COT THETA/CSC THETA IS EQUAL TO?
Each verb below, one noun does not go with it. Which one? 1/ discover ( the truth, a cure, DNA, gold ) 2/ make ( cars, a discovery, a phone call ) 3/ tell ( hel
Which of the following is x⁴ + y⁴ identically equal to? (A) (x² + y²)(x + y)(x - y) (B) (x² + xy + y²)(x² - xy + y²) (C) (x² + √2xy + y²)(x² - √2xy + y²) (D) (x