Question

Which are the solutions of the equation x^4-5x^2-14=0? Use factoring to solve.

Answer 1

x = ±√7 and x=±i√2

Explanation:

x^4-5x^2-14=0

Factor

(x^2 - 7) ( x^2 +2) =0

Using the zero product property

x^2 -7 =0 x^2 + 2 =0

x^2 =7 x^2 = -2

Taking the square root of each side

(x^2)^1/2 =7^1/2 ( x^2)^1/2 = (-2)^1/2

x = ±√7 x=±i√2