Let g (x) = 2x + 3, G (x + 2) = f (x), then f (x)=______ ．

Let g (x) = 2x + 3, G (x + 2) = f (x), then f (x)=______ ．

∵ g (x) = 2x + 3, G (x + 2) = f (x), ∵ f (x) = g (x + 2) = 2 (x + 2) + 3 = 2x + 7, so the answer is: 2x + 7

Given f (x-1) = x ^ 2-2x + 7, find the analytic expressions of F (x) and f (x + 1)
I don't understand the following answer,

For the sake of simplicity, the method is simplified
f(x-1)=x^2-2x+1+6=(x-1)^2+6
Let X-1 = y
x=y+1
Then f (x-1) = f (y) = y ^ 2 + 6
So f (x) = x ^ 2 + 6
Let X-1 = y + 1
Then x = y + 2
So f (x-1) = f (y + 1) = (y + 2-1) ^ 2 + 6
=(y+1)^2+6
=y^2+2y+1+6
=y^2+2y+7
So f (x + 1) = x ^ 2 + 2x + 7

Who is the greatest common factor of 18 and 23?

1|18 23
———
18 23
So the greatest common factor is 1 * 18 * 23 = 414

Let a > b > 0, then the minimum value of A2 + 1ab + 1a (a-b) is ()
A. 1B. 2C. 3D. 4

A2 + 1ab + 1a (a-b) = AB + 1ab + a (a-b) + 1a (a-b) ≥ 4 if and only if AB = 1aba (a-b) = 1a (a-b) takes the equal sign, that is, a = 2B = 22 takes the equal sign

What is the second derivative of y = ln [3x / (1 + 2x)]

y=ln(3x/(1+2x))=ln3x-ln(1+2x)
y′=3/3x-2/(1+2x)=1/x-2/(1+2x)
y′′=-1/x^2 + 4/(1+2x)^2

How to calculate 243-39-61 in a simple way

243-39-61=243-(39+61)=243-100=143

What's the difference between 325 minus 135 divided by 9

325-（135÷9）
=325-15
=310

How does 3x + 5 = 2x + 10 calculate asdasdasd

3X+5=2X+10
3X-2X=10-5
1X =5
X=5

How to calculate 103 times 23 in a simple way

103×23
=100×23+3×23
=2300+69
=2369

If n is a positive integer, the value of (n + 11) ^ 2-N ^ 2 can always be divided by K

(N+11)^2 - N^2 = km
(N+11+ N)(N+11-N) = km
(2N+11)*11 = km
N is a positive integer, and the square of (n + 11) minus the square of n is always divisible by K
х k = 11, or K = 2n + 11, where n = 1,2,3