Question

factorise :- 9x^2-(x^2-4)^2
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Answer 1

9x² - (x² - 4)²

= (3x)² - (x² - 4)²

= [(3x) - (x² - 4)][(3x) + (x² - 4)]

= (3x - x² + 4)(3x + x² - 4)

= (-x² + 3x + 4)(x² + 3x - 4).

Answer 2

Hello Friend.

Here is ur answer below,,

$9x {}^{2} - (x {}^{2} - 4) {}^{2} \\ = > 9x {}^{2} - (x {}^{4} + 16 - 8x {}^{2} ) \\ = > 9x {}^{2} - x {}^{4} - 16 + 8x {}^{2} \\ = > - x {}^{4} + 17x {}^{2} - 16 \\ = > - x {}^{4} + 16x {}^{2} + x {}^{2} - 16 \\ = > - x {}^{2} (x {}^{2} - 16) + 1(x {}^{2} - 6) \\ = > ( - x {}^{2} + 1)(x {}^{2} - 16) \\ = > ( - x + 1)(x + 1)(x + 4)(x - 4)$

I hope that helps you,