x2 + y2 + z2 + 2xy – 2yz – 2zx = 

A) (x + y + z)2 

B) (x – y + z)2 

C) (x + y – z)2 

D) (x – y – z)2

4 views

2 Answers

Correct option is (C) (x + y – z)2

\(x^2+y^2+z^2+2xy-2yz-2zx\) \(=x^2+y^2+(-z)^2+2\times x\times y\) \(+2\times y\times-z+2\times-z\times x\)

\((x+y-z)^2\)

4 views

C) (x + y – z)2

4 views