Advertisements
Advertisements
Question
Factorise: x4 - 5x2 - 36
Advertisements
Solution
x4 - 5x2 - 36
= (x2)2 - 5x2 - 36
= (x2)2 - 9x2 + 4x2 - 36 ...{∵ -36 = -9 × 4 }
{-5 = -9 + 4}
= x2 (x2 - 9) + (x2 - 9)
= (x2 - 9)(x2 + 4)
= [x2 - (3)2] [x2 + 4]
= (x + 3)(x - 3)(x2 + 4)
= (x2 +4) (x + 3)(x - 3)
APPEARS IN
RELATED QUESTIONS
Factorise the following expression:
20 l2m + 30 alm
Factorise the following expression:
5x2y − 15xy2
Factorise.
x2 + xy + 8x + 8y
Factorize the following:
3x − 9
Factorize the following:
20a12b2 − 15a8b4
Factorize the following:
28a2 + 14a2b2 − 21a4
Factories by taking out common factors :
2x(a - b) + 3y(5a - 5b) + 4z(2b - 2a)
Factorise:
`x^2 + [a^2 + 1]/a x + 1`
Factorise:
`x^4 + y^4 - 27x^2y^2`
Factorise : `x^2 + 1/x^2 - 3`
Factorise : 9x 2 + 3x - 8y - 64y2
Factorise : 17a6b8 - 34a4b6 + 51a2b4
factorise : 8(2a + 3b)3 - 12(2a + 3b)2
factorise : a2 - ab - 3a + 3b
Factorise the following by taking out the common factors:
5a(x2 - y2) + 35b(x2 - y2)
Factorise the following by taking out the common factors:
12a3 + 15a2b - 21ab2
