Question

Viet moi bieu thuc sau ve dang tong hoac hieu 2 binh phuong:

a) (x+y+4)(x+y-4)

b)(x-y+6)(x+y-6)

Answer 1

a) \(\left(x+y+4\right)\left(x+y-4\right)=\left(x+y\right)^2-4^2\)

b)\(\left(x-y+6\right)\left(x+y-6\right)=\left[x-\left(y-6\right)\right]\left(x+y-6\right)=x^2-\left(y-6\right)^2\)

Answer 2

\(a,\left(x+y+4\right)\left(x+y-4\right)\)
\(=\left(x+y\right)^2-4^2\)
\(b,\left(x-y+6\right)\left(x+y-6\right)\)
\(=x^2-\left(y-6\right)^2\)