Expand (i) \((u – v) (u + v)\), (ii) \((u – v) (u^{2}+ uv + v^{2})\) and (iii) \((u – v)(u^{3}+ u^{2}v + uv^{2}+ v^{3})\), Do you see a pattern? What would be the next identity in the pattern that you see? Can you check it by expanding?
 
Answer:
 
 (i) \((u – v) (u + v)\) \(=\) iiii
 
(ii) \((u – v) (u^{2}+ uv + v^{2})\) \(=\) iiii
 
(iii) \((u – v)(u^{3}+ u^{2}v + uv^{2}+ v^{3})\) \(=\) iiii
 
Do you see a pattern in the above expansion?
 
The next identity in the pattern is uvii+iii+iiii+iiiii.
 
The expansion of the above found identity is iiii.