T = x2 + 2xy + y2 - 2x - 2y - 1
= (x + y)2 - 2(x + y) + 1 - 2
= (x + y - 1)2 - 2 \(\ge\)-2
Dấu "=" xảy ra <=> x + y - 1 = 0
=> x + y = 1
Vậy Min A = -2 <=> x + y = 1
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Exam number 219:12
Fill in the blank with the suitable number (Note: write decimal number with "the dot" between number part and fraction part. Example: 0.5)
Question 1:
Given .
Find the value of "" such that its degree is equal to 4.
Answer: The value of "" is
Question 2:
The value of with is
Question 3:
Given .
The degree of is
Question 4:
Given .
The degree of is
Question 5:
Given .
The value of is
Question 6:
In this figure, if the length of the line segment is an even number.
Then .
Question 7:
Given .
The value of
Question 8:
The value of with is
Question 9:
Given with .
Then the minimum of is
Question 10:
The minimum value of is
If 2a+b = 8, a>b and (a-b)^2 =1 then what is tha value of 2ab