Question

factorise the following 15 x ki power 4 + 3 x square - 18​

Answer 1

The factorisation of $15x^4+3x^2-18$ is equal to$3(5x^2+6)(x^2-1)$.

Step-by-step explanation:

We have,

$15x^4+3x^2-18$

To find, the factorisation of $15x^4+3x^2-18$ = ?

∴ $15x^4+3x^2-18$

Taking 3 as common, we get

$3(5x^4+x^2-6)$

Let $x^{2} =a$

$=3(5a^2+a-6)$

$=3(5a^2+6a-5a-6)$

= 3[5a(a - 1) + 6(a - 1)]

= 3(5a + 6)(a - 1)

Put $x^{2} =a$, we get

$=3(5x^2+6)(x^2-1)$

∴ The factorisation of $15x^4+3x^2-18$ $=3(5x^2+6)(x^2-1)$

Thus, the factorisation of $15x^4+3x^2-18$ is equal to$3(5x^2+6)(x^2-1)$.