Question

因式分解x2+4xy-4y2 x2-2（根号2）x-3

Answer 1

x2+4xy-4y2

=(x^2+4xy+4y^2)-8y^2

=(x+2y)^2-8y^2

=(x+2y+2√2y)(x+2y-2√2y)

x2-2（根号2）x-3

=x^2-2√2x+2-5

=(x-√2)^2-5

=(x-√2+√5 )=(x-√2-√5)