Question

resolve into factors 8a⁴+2a²-45​

Answer 1

Step-by-step explanation:

$8a {}^{4} + 2a {}^{2} - 45 \\ = 8a {}^{4} + 20a {}^{2} - 18a {}^{2} - 45 \\ = 4a {}^{2} \times (2a {}^{2} + 5) - 9(2a {}^{2} + 5) \\ = (2a {}^{2} + 5) \times (4a {}^{2} - 9) \\ = (2a {}^{2} + 5) \times (2a - 3) \times (2a + 3)$

Answer 2

= 8a^4 + 20a^2 - 18a^2 - 45
= 4a^2 x (2a^2 + 5) - 9(2a^2 + 5)
= (2a^2 + 5) x (4a^2 - 9)
= (2a^2 + 5) x (2a - 3) x (2a + 3)