Question

y4+4y2-32. Factorise​

Answer 1

Step-by-step explanation:

$y {}^{4} + 4y {}^{2} - 32 \\ taking.y {}^{2} = a \\ therefor \\ a {}^{2} + 4a - 32 \\ a{}^{2} + 8a - 4a - 32 \\ a(a + 8) - 4(a + 8) \\ (a + 8)(a - 4) \\ putting \: \: a = y {}^{2} \\ (y { }^{2} + 8)(y {}^{2} - 4) \\ (y {}^{2} + 8)(y {}^{2} - 2 {}^{2} ) \\ (y {}^{2} + 8)(y - 2)(y + 2)$