Solve [tex]$x^4 - 17x^2 + 16 = 0$[/tex]

1. Let [tex]$u = x^2$[/tex].

2. Rewrite the equation in terms of [tex][tex]$u$[/tex][/tex].

[tex]$u^2 - 17u + 16 = 0$[/tex]

3. Factor the equation.

[tex]$(u - 16)(u - 1) = 0$[/tex]

4. Solve for [tex]u[/tex].

[tex]u = 16[/tex] or [tex]u = 1[/tex]

5. Solve for [tex]x[/tex] in the original equation.

[tex]x^2 = 16[/tex] or [tex]x^2 = 1[/tex]

[tex]x = \pm 4[/tex] or [tex]x = \pm 1[/tex]

Select all of the solutions to the original equation:

[tex]x = 4[/tex]
[tex]x = -4[/tex]
[tex]x = 1[/tex]
[tex]x = -1[/tex]



Answer :

Sure, let's solve the equation [tex]\( x^4 - 17x^2 + 16 = 0 \)[/tex] step by step.

1. Substitute [tex]\( u = x^2 \)[/tex]:
By substituting [tex]\( u = x^2 \)[/tex], we can rewrite the equation in terms of [tex]\( u \)[/tex]:
[tex]\[ x^4 - 17x^2 + 16 = 0 \implies u^2 - 17u + 16 = 0 \][/tex]
This substitution simplifies the quartic equation into a quadratic equation.

2. Factor the quadratic equation:
We need to factor [tex]\( u^2 - 17u + 16 = 0 \)[/tex]:
[tex]\[ u^2 - 17u + 16 = (u - 16)(u - 1) = 0 \][/tex]
This factorization shows that the solutions for [tex]\( u \)[/tex] are [tex]\( u = 16 \)[/tex] and [tex]\( u = 1 \)[/tex].

3. Solve for [tex]\( x \)[/tex] by substituting back [tex]\( u = x^2 \)[/tex]:
- For [tex]\( u = 16 \)[/tex]:
[tex]\[ x^2 = 16 \implies x = \pm 4 \][/tex]
- For [tex]\( u = 1 \)[/tex]:
[tex]\[ x^2 = 1 \implies x = \pm 1 \][/tex]

4. Collect all solutions:
The complete set of solutions for [tex]\( x \)[/tex] is:
[tex]\[ x = 4, x = -4, x = 1, x = -1 \][/tex]

So, the solutions to the original equation [tex]\( x^4 - 17x^2 + 16 = 0 \)[/tex] are:
[tex]\[ x = 4, x = -4, x = 1, x = -1 \][/tex]