Question

What is the expansion of $(m-n{)}^2$ ?

• A. $m^2-2mn+n^2$
• B. $m^3-2mn+n^2$
• C. $m^2-4mn+n^2$
• D. $m^2-2mn-n^2$

Answer 1

The correct option is A $m^2-2mn+n^2$

We have the identity,
${(a-b)}^2=a^2-2ab+b^2$

So, ${(m-n)}^2=m^2-2mn+n^2$