Answer:
Step-by-step explanation:
x4 + 4x² – 45 = x^4 + 4x^2 - 45. Use " ^ " to indicate exponentiation.
Temporarily substitute p for x^2. Then we have:
p^2 + 4p - 45, or
(p + 9)(p - 5)
But p = x^2.
Therefore, our expression becomes
(x^2 + 9)(x^2 - 5)
We could stop here or we could factor further.
Hint: x^2 - 5 = (x - √5)(x + √5); (x^2 + 9) factors into imaginary roots.
