Foctorise the following:x4 – 5x2 + 4

⇒ x4 - 5x2 + 4⇒ x4 - 4x2 – x2 + 4⇒ x2(x2 - 4) - (x2 - 4)⇒ (x2 - 4)(x2 - 1)⇒ (x2 – 22)(x2 – 12) ⇒ (x – 2)(x + 2)(x – 1)(x + 1)

Q3 of 53 Page 166

Foctorise the following:
x⁴ – 5x² + 4

⇒ x⁴ - 5x² + 4

⇒ x⁴ - 4x² – x² + 4

⇒ x²(x² - 4) - (x² - 4)

⇒ (x² - 4)(x² - 1)

⇒ (x² – 2²)(x² – 1²)

⇒ (x – 2)(x + 2)(x – 1)(x + 1)

Foctorise the following:

x² + 4x – 21

Foctorise the following:

x² – 4x – 192

Foctorise the following:

x⁴ – 13x²y² + 36y⁴.

Foctorise the following:

2x² + 7x + 6

Questions · 53

4. Factorisation

1 2 2 2 2 3 3 3 3 3 3 1 1 1 1 1 1 2 2 2 2 2 2 3 3 3 3 3 3 1 1 1 1 1 1 2 3 3 3 3 3 3 3 4 4 4 4 4 5 5 5 5 6