Question

1
5. If x, y, z are in AP, then the value of
(x + y - z) (y + z - x) is equal to
(1) Syz - 3y2 - 4z2 (2) Syz - 3z2 - 4y2
(3) Xyz + 3y2 - 4z2
(4) Syz - 3y2 + 4z2​

Answer 1

Answer:

Option 1 is correct

Step-by-step explanation:

x,y and z are in AP, then 2y=x+z

Substituting x as 2y−z in the above expression, we get

(x+y−z)(y+z−x)

=(2y−z+y−z)(y+z−2y+z)

=(3y−2z)(−y+2z)

=6yz−3y^2 −4z^2 +2yz

=8yz−3y^2−4z^2