Question

factorise x4+3x2-28​

Answer 1

Answer: middle term split is used in this question.

Step-by-step explanation:

Answer 2

You will have to spilt the middle term here:

x^4+3x^2-28

x^4 + 7x^2 - 4x^2 - 28

x^2(x^2+7) - 4(x^2+7)

=(x^2-4)(x^2+7)