Question

(x+y+z)^2 - (x-y-z)^2 + 4y^2 - 4z^2
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Answer 1

Answer:

3 (x² + y² + z²) + 2 (xy − yz + xz)

Step-by-step explanation:

Formula used:- (a + b + c)² = a² + b² + c² (ab + be + ca)

Hence,

x² + y² + z² + 2 (xy + yz +zx) + x² + y² +z²+2(-xy)

− yz + xz + x² + y² + z² + 2 (xy - yz -xz) 3x² + 3y² + 3x² + 2xy - 2yz + 2xz

= 3 (x² + y² + z²) + 2 (xy − yz + xz)

Therefore, solution is:-

3 (x² + y² + z²) + 2 (xy − yz + xz)

Hope it helps! :)

Answer 2

Answer:

3 (x² + y² + z²) + 2 (xy − yz + xz)

Step-by-step explanation:

Formula used:- (a + b + c)² = a² + b² + c² (ab + be + ca)

Hence,

x² + y² + z² + 2 (xy + yz +zx) + x² + y² +z²+2(-xy)

− yz + xz + x² + y² + z² + 2 (xy - yz -xz) 3x² + 3y² + 3x² + 2xy - 2yz + 2xz

= 3 (x² + y² + z²) + 2 (xy − yz + xz)

Therefore, solution is:-

3 (x² + y² + z²) + 2 (xy − yz + xz)