Given the function FX = x2 + 1, and GX = f [f (x)], G (x) = g (x)-

Given the function FX = x2 + 1, and GX = f [f (x)], G (x) = g (x)-

G (x) = f (f (x)) = f (x2 + 1) = (x ^ 2 + 1) ^ 2 + 1 = x ^ 4 + 2x ^ 2 + 2, the following g (x) is not fully questioned: given the function FX = x2 + 1, and GX = f [f (x)], G (x) = g (x) - 2AF (x), if a = 3, find the minimum value of G (x): G (x) = g (x) - 6F (x) = x ^ 4 + 2x ^ 2 + 2-6x ^ 2-6 = x ^ 4-4x ^ 2-4 =

Given the function FX = x2-2x, GX = x2-2x (x ∈ [2,4]}), find the monotone interval of FX and the minimum value of FX and GX

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Although the expressions of F (x) and G (x) are the same, they are two different functions with different domains
Then: F (x) = x ^ 2-2x = (x-1) ^ 2-1, which means that the opening is upward, the vertex is (1, - 1), and the axis of symmetry is a parabola of x = 1. Therefore, the function f (x) monotonically decreases on (negative infinity, 1), monotonically increases on (1, positive infinity), and the minimum value is - 1;
When the monotone increasing interval of G (x) = x ^ 2-2x (x belongs to [2,4]) is [2,4], and the minimum value is x = 2, then G (x) = 0
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The following functions are the same: () (a) f (x) = x + 1, (g) x = x & # 710; 2-1 / X-1 (b) f (x) = x, G (x) = (root x)&
(C)f(x)=sinˆ2 x+cosˆ2 x,g(x)=1 (D)f(x)=INxˆ2,g(x)=2 INx

Judge from two points
1: The corresponding rule is equivalent
2: Same domain
Choose C