#### Question

Solve x^{4} – 10x^{2} +9 =0

#### Solution

x^{4} – 10x^{2} +9 =0

`=> x^4 - 9x^2 - x^2 + 9 = 0`

`=> x^2(x^2 - 9) - 1(x^2 - 9) = 0`

`=> (x^2 - 9)(x^2 - 1) = 0`

If `x^2 - 9 = 0` or `x^2 - 1 = 0`

`=> x^2 =9` or `x^2 = 1`

`=>x = +- 3 or x = +-1`

Is there an error in this question or solution?

Solution Solve X4 – 10x2 +9 =0 Concept: Quadratic Equations.