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If the value range of function y = ln [(a ^ 2-4) x ^ 2 + (A-2) x + 1 / 2] is r, then the value range of real number a is?
∵ the value range of the function is r
∴f(x)=(a^2-4)x^2+(a-2)x+1/2>0
(1) If a ^ 2-4 = 0, i.e. a = ± 2, f (x) = (a ^ 2-4) x ^ 2 + (A-2) x + 1 / 2 = 1 / 2, then y is a fixed value and does not meet the condition
(2) If a ^ 2-4
Let the function FX = x2 + X-1 / 4, if the domain is [a, a + 1], the range of FX is [- 1 / 2,1 / 16], and the value of a is obtained
If FX = x & # 178; + X-1 / 4 is formulated first, FX = (x + 1 / 2) &# 178; - 1 / 2 is obtained, which is a parabola with the opening upward and the axis of symmetry x = - 1 / 2, and the minimum value is y = - 1 / 2
Given the function FX = (1 + x) ^ (1 / 2) + (1-x) ^ (1 / 2), find the function definition and range
From 1 + x > = 0, 1-x > = 0, the function domain is [- 1,1]
Let u = (1 + x) ^ (1 / 2), v = (1-x) ^ (1 / 2),
Then u > = 0, V > = 0, and U + V = y, u ^ 2 + V ^ 2 = 2,
Let u = √ 2cos (a), v = √ 2Sin (a), where 0
The range of function y = ln (1-x2) is______ ．
In order to make the function meaningful, then 1-x2 > 0, the solution is - 1 < x < 1, at this time 0 < 1-x2 < 1, ln (1-x2) ≤ 0, that is, the value range of the function is (- ∞, 0], so the answer is: (- ∞, 0]
For example, there is a - sign before the absolute value of a - | 1-A | (a is greater than 0). Should the number in the absolute value change its sign, such as A-A + 1
Such as the title
Remember: the absolute value is the distance from a number to the origin. How can the distance be negative
Therefore, no matter whether the absolute value sign is positive or negative, once it leaves the absolute value sign, it will become positive
If it's positive, it's positive
If it's negative inside, after the absolute value sign is removed, it will become its opposite number, that is, positive
Also ah: absolute value priority is greater than the + - sign, so you must first deal with the absolute value sign, and then consider the negative sign
If a is greater than the absolute value of B, then A-B is
Because a > IBI,
So,
When b > 0, a > b, so A-B > 0
When B-B,
And because of B0,
a>0
So A-B > 0
So A-B is a positive number
If a is less than 0, B is greater than 0 and the absolute value of a is greater than the absolute value of B, try to connect the four numbers a, - A, B. - B with the less than sign
A is less than 0 a negative number B is more than 0 positive number
The absolute value of a is greater than that of B. the number of a (not counting sign) is greater than that of B
Then you can line up
If you don't understand, you can use numbers now
For example, if a = - 5, then the number of B is smaller than a, and then the positive number is 3
So a = - 5 - a = 5, B = 3 - B = - 3
You can arrange a
-The opposite number of (- 9), absolute value
-The opposite number of (- 9) is - 9,
-The absolute value of (- 9) is 9
Why the absolute value of - 6 is 6, and the numbers with absolute value of 6 are - 6 and + 6,
|-6 | = 6 specifies that the absolute value of any number is non negative, so it is 6
Because | 6 | = 6 and | - 6 | = 6, numbers with absolute value of 6 are 6 and - 6
-|-6|=6
What is the sum of the difference between the opposite numbers of negative a and negative B and the absolute value of positive C
A-B+C
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