Question

Factorise
2y-y^2-1+x^4

Answer 1

Answer:

Rearrange the terms as follows:

x^2 — y^2 — 2y — 1

Group the last three terms, factoring out a —1:

x^2 — (y^2 + 2y + 1)

Those last three terms are a perfect square:

x^2 — (y + 1)^2

Now you have the difference of two squares:

[x — (y + 1)][x + (y + 1)]

Remove the inner grouping symbols to get

(x — y — 1)(x + y + 1)