Question

Factorise [5r+2/3]square -[2r-1/3] square

Answer 1

(5r+2/3)^2-(2r-1/3)^2

Let,

5r+2/3=a,

2r-1/3=b.

Using identity:

a^2-b^2=(a+b)(a-b)

=[(5r+2/3)+(2r-1/3)][(5r+2/3)-(2r-1/3)]

=[5r+2/3+2r-1/3][5r+2/3-2r+1/3]

=[7r+1/3][3r+1]

Answer 2

Answer:

=[7r+1/3][3r+1]

Step-by-step explanation:

Using identity:

a^2-b^2=(a+b)(a-b)

=[(5r+2/3)+(2r-1/3)][(5r+2/3)-(2r-1/3)]

=[5r+2/3+2r-1/3][5r+2/3-2r+1/3]

=[7r+1/3][3r+1]