Question

expand (x-2y+1)^2
please do it faster​

Answer 1

Answer:

(a+b+c)^2=a^2+b^2+c^2+2ab+2bc+2ca,

(x-2y+1)^2=x^2+(-2y)^2+1^2+2(x)(-2y)+2(-2y)(1)+2(1)(x),

=x^2+4y^2+1-4xy-4y+2x