Question

Factorise a^4 +3a^2+4 by a^2 -b^2 formula
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Answer 1

Answer:

a = + or - 1 and also a = -√4

Step-by-step explanation:

We have

=> a⁴ + 3a² + 4 = 0

Here let a² = x

=> x² + 3x + 4 = 0

=> x² + 4x - x + 4 = 0

=> x(x + 4) - (x + 4) = 0

=> (x - 1)(x + 4) = 0

Thus x = 1 or x = - 4

Then a² = 1 or a² = -4

=> a = 1 or a = -1 or a = √-4

Hope this helps