Given the function f (x) = (1 / 4 ^ x) - (1 / 2 ^ x) + 1, X ∈ [- 3,2], find the maximum and minimum of F (x)

Given the function f (x) = (1 / 4 ^ x) - (1 / 2 ^ x) + 1, X ∈ [- 3,2], find the maximum and minimum of F (x)

Answer: Minimum: 3 / 4, maximum: 57
Let t = 1 / 2 ^ x, then f (x) = T ^ 2-T + 1
Because x ∈ [- 3,2], t ∈ [1 / 4,8]
Because f (x) is a quadratic function of one variable with 1 / 2 symmetry
So when t = 1 / 2, the minimum value of F (x) is 3 / 4
When t = 8, the maximum value of F (x) is 57