Question

factorise 15x⁴+3x²-18
please do this I will mark you brainlist​

Answer 1

Step-by-step explanation:

15x^4+3x^2-18

15(x^2)^2 +3x^2-18

let x^2=a

15a^2+3a-18

3[5a^2+a-6]

3[5a^2+6a-5a-6]

3[5a^2-5a+6a-6]

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

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

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

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

Answer 2

Solution

Given ,

• 15x^4 +3x^2 -18

To find ,

• we have to find the value of the equation given.

How to solve this ,

• we can solve this by middle splitting method

$\bold{15 {x}^{4} + 3x ^{2} - 18}$

$= > 3( {5x}^{4} + {x}^{2} - 6)$

$= > 3(5x ^{4} + 6 {x}^{2} - {5x}^{2} - 6)$

$= > 3( {x}^{2} (5x ^{2} + 6) - ( {5x}^{2} + 6))$

$= > 3( {5x}^{2} + 6) \times ( {x}^{2} - 1)$

$\bold {= > 3( {5x}^{2} + 6)( {x}^{2} - 1)( {x}^{2} + 1)}$ [ by using the formula a^2-b^2 = (a+b)(a-b) ]

The value of the equation is 3(5x^2+6)(x^2-1)(x^2+1) .

✨Additional information

• (X+a)(X+b) = x ^2 + (a+b)X + ab
• (X+y)^2 = x^2 +y ^2 + 2xy
• (x-y)^2 = x^2 +y^2 -2xy