Question

please refer the image for question​

Answer 1

Step-by-step explanation:

(q-r)2+(r-p)2+(s-q)2

=q2-r2+r2-p2+s2-q2

=s2-p2

=(p-s)2.

In the second step the q2and -q2are cancelledand then the r2and -r2are cancelled remainig p2 and -s2 can write on third step