Factoring a polynomial/simplifying
I have an test tomorrow. I studied everything..but i know my teacher will give us hard questions he did not even solve in the class..
how to factor this polynomial:
4y^2 - 81
i know that a^2 - b^2 = (a-b) (a+b)
(m^2 n ^3)^-2 (m^-3 n^2)^-3
we learned that if we have (m^2 m^3)^2 then the answer is m^2 n^3 x m^2 n^3 but how about if we have a -ve square or -3?
Simplify a radical:
√8 + √18
according to my teacher the solution is..
= √(2x2x2) + √(3x3x3)
=2√2 + 3√2
how is that possible? :confused:
Thanks in advance :)