x ∈ [4,6) means:
4 < x < 6
4 < x ≤ 6
4 ≤ x < 6
4 ≤ x ≤ 6
x ∈ [ 4 means x is greater than or equal to 4.
and x ∈ 6) means x is lesser than 6.
So, x ∈ [4,6) means: 4 ≤ x < 6
The image of point (4, -6) under the operation Mx.My is
Given f(x) = 4x - 6. Find the value of f(3)