The values of αfor which the system of equations x + y + z = 1, x + 2y + 4z = a, x + 4y + 10z =α2 is consistent, are given by
1, – 2
– 1, 2
1, 2
none of these
Subtracting first equation from the second and third, we get
y+3z=α−1
3y + 9z = a2 – 1
∴ α2−1=3(α−1)⇒α=1or α=2