Question

Factorise the following using suitable identities
1. a sq + 2ab + b sq - 9
2. 2x sq + y sq+ 8z sq - 2 root 2 xy + 4 root 2 yards-8 xz
3. 64a cube - 27b cube - 144 a sq + 108 ab sq
4. 27 x cube + y cube - z cube + 9xyz

Answer 1

1. (a+b)^2-3^2=(a+b+3)(a+b-3)
3. (4a-3b)^3