Factorise :
(ax+by)2+(bx−ay)2
(ax+by)2+(bx−ay)2=a2x2+b2y2+2abxy+b2x2+a2y2−2abxy=a2x2+b2y2+b2x2+a2y2=a2x2+b2x2+a2y2+b2y2=x2(a2+b2)+y2(a2+b2)=(a2+b2)(x2+y2) Ans.
Factorise by grouping method: