Question

Factor m^4-9n^4

Answer 1

You cant there are no common facotrs

Answer 2

this is basically the difference of 2 squares...

\[(a -b)(a + b) = a^2 - b^2\]

you need to identify a and b

Answer 3

So would it be (m^2-3n^2) and (m^2+3n^2)

Answer 4

yes... but

\[m^2 - 3n^2\]

is still the difference of 2 squares

Answer 5

So is that the answer times 2

Answer 6

well the 1st factorisation is

\[(m^2 - 3n^2)(m^2 + 3n^2)\]

the 1st binomial is still the difference of 2 squares so its

\[(m - \sqrt{3}n)(m + \sqrt{3}n)(m^2 + 3n^2)\]