book shows answer as x^4+4x^2y^2+4y^4-4x^2y^2=(x^2+2y^2)^2-(2xy)^2=(x^2+2y^2-2xy)(x^2+2y^2+2xy) What is happening here and what steps am i missing???
Follow Math Help Forum on Facebook and Google+
Originally Posted by sluggerbroth book shows answer as x^4+4x^2y^2+4y^4-4x^2y^2=(x^2+2y^2)^2-(2xy)^2=(x^2+2y^2-2xy)(x^2+2y^2+2xy) What is happening here and what steps am i missing??? note these terms form a perfect square ... now you have the difference of two squares ...
What they have done is add and subtract which, of course, doesn't change the actual value. But that does change the form so that it we can think of it as which is a "difference" of two squares. You probably know that so that last is .
they just add ( and subsequently subtract ) 4x^2y^2 because it forms a perfect square?
another example ... let's say you wish to factor
View Tag Cloud