Let X be less than 0, then the minimum value of y = 3-3x-x / 4 is 0

Is it like this, y = 3-3x - (4 / x)

Finding the minimum value of function y = 3x + 4 / x ^ 2 (x > 0)
Why do you divide 3x into 2 / 3x and 2 / 3x when you do this topic? Why do you split it like this? Why are there three numbers? It's obviously two numbers

y=3x+4/x^2
=3/2x+3/2x+4/x²≥3³√(9/4*4)=3³√9
If and only if 3 / 2x = 4 / X & # 178; that is, X & # 179; = 3 / 8, the equal sign holds
This example uses the mean inequality of three positive numbers
a,b,c>0
a+b+c≥3³√(abc)
If and only if a = b = C, the equal sign holds
The condition of using the mean value theorem is
1. The original is in accordance with the law
2 & # 186; fixed: if two numbers, 3x * 4 / X & # 178; = 12 / x, are not fixed, then x is divided into two equal numbers, 3 / 2x, so that the product is fixed
3x must be divided into two equal numbers to make the three decomposed numbers equal
If we write 3x as 3x = x + 2x
Then 3x + 4 / X & # 178; = x + 2x + 4 / X & # 178; > 3 & # 179; √ 8
(because x ≠ 2x, the equal sign cannot be removed. If the equal sign does not hold, there will be no minimum value.)

The absolute value of X - (2 / 3 + 1) = 1
There is a simple way

Mathematical answer group for you to answer, I hope to help you
∣x-(2/3+1)∣=1
x-5/3=±1
X = 8 / 3 or 2 / 3

Question 1: absolute value of - 2 / 7 - (- 1 / 2) + 2-1 and 1 / 2 question 2: 2 (x + 3) - 5 (1-x) = 3 (X-2) question 3: 1-x / 3-x-1 / 2 = 1
Question 4: 3 [X-2 (X-2)] > x-3 (X-2)
Question 5: 3x-2 / 3-9-2x

Is this a calculation problem?
1. Where is the absolute value? If it's outside, the answer is 5 / 7. If it's between - 1 and 1 / 2, the answer is 26 / 7
2.x=-7/5
3.x=3/8
4.x=-61/24

Let X be less than 0, then the minimum value of y = 3-3x-x / 4 is 0