Question

What substitution should be used to rewrite x8 – 3x4 + 2 = 0 as a quadratic equation?

Answer 1

Answer:

Substitute y for x^4.

Step-by-step explanation:

Let y = x^4 then:

y^2 - 3y + 2 = 0.

Answer 2

Answer:

$y^2 - 3y + 2 =0$ is the required quadratic equation.

Step-by-step explanation:

We are given the following equation in the question:

$x^8 - 3x^4 + 2 =0$

We need to make a substitution such that the above equation becomes a quadratic equation.

We make the substitution $y = x^4$

$x^8 - 3x^4 + 2 =0\\\Rightarrow (x^4)^2 - 3x^4 + 2 = 0\\\Rightarrow y^2 - 3y + 2 =0$

$y^2 - 3y + 2 =0$ is the required quadratic equation.