Question

factorise 3x^7y-81x⁴y⁴​

Answer 1

Answer:

3x

7

y−81x

4

y

4

=3x

4

y(x

3

−27y

3

)

=3x

4

y(x

3

−(3y)

3

)

Using a

3

−b

3

=(a−b)(a

2

+ab+b

2

),we get

3x

4

y(x−3y)(x

2

+x(3y)+(3y)

2

)

=3x

4

y(x−3y)(x

2

+3xy+9y

2