If the quadratic function f (x) = x ^ 2 - (a + 1) x + 5 is monotone in the interval (1 / 2,1), the value range of F (2) is obtained

If the quadratic function f (x) = x ^ 2 - (a + 1) x + 5 is monotone in the interval (1 / 2,1), the value range of F (2) is obtained

According to the meaning of the problem, the equation of the axis of symmetry of the quadratic function f (x) is x = (a + 1) / 2, because it is a monotone function in the interval (1 / 2,1), so there is (a + 1) / 2 = 1, so a = 1 and f (2) = 7-2a, so f (2) = 7. Note: according to the range of a, find out the range of - A, - 2A, and 7 + (- 2A)

We came to the park with light steps and loud songs

We came to the park with light steps and singing songs - because "loud songs" can't be walked

4(m+n)²-(m-n)²=?(y²-1)²-6(y²-1)+9=?
X & # 178; = the square of X

4(m+n)²-(m-n)²=[2(m+n)]²-(m-n)²=[2(m+n)+(m-n)][2(m+n)-(m-n)]=(3m+n)(m+3n)(y²-1)²-6(y²-1)+9=[(y²-1)-3]²=(y²-4)²=[(y+2)(y-2)]²=(y+2)²(y-2...

The odd function f (x) = A-1 / 2 ^ x + 1 defined on all real numbers. If the inverse function is less than 1, the value of X is taken

∵ f (x) is an odd function
∴f(-x)=-f(x)
∴f(x)+f(-x)=0
When x = 0, f (0) = 0
So 0 = A-1 + 1, that is a = 0
If the value of the inverse function is less than 1
As long as X of the original function

Mom said on the phone, "Ning Ning, mom is going to work overtime. You can eat by yourself first."
Please answer! Is it passer-by a telling Ning Ning, or Ning Ning to passer-by a saying?

Mother on the phone to Ningning said she would work overtime, let Ningning eat first
Indirect reporting is to describe two persons from the perspective of the third party

It is known that the equation - x2 + 2x = | A-1 | on X ∈ (12,2] has real roots, then the value range of real number a is______ ．

Since the function f (x) = - x2 + 2x = - (x-1) 2 + 1 ≤ 1, the range of function f (x) is (- ∞, 1]. According to the known equation - x2 + 2x = | A-1 | on X ∈ (12,2], the image of X and the image of straight line y = | A-1 | always have real roots on X ∈ (12,2], as shown in the figure: therefore, there are | A-1 | ≤ 1

Mathematics in grade one of senior high school~
If the period of y = f (x) is 3, try to find the period of y = f (2x + 1)
Why can I write X in y = f (2x + 1 + 3) as the original x? If not, why can I change it

Y = f (x) period is 3
f(x)=f(x+3)
F (2x + 1) = f (2x + 1 + 3) = f (2 (x + 3 / 2) + 1) x becomes x + 3 / 2
The cycle is 3 / 2

There are four kinds of ABCD books in the library. Each person can borrow one or two books. At least (?) people borrow books. There must be two people who borrow the same books
Such as the title
also:
Each person can borrow 1-4 books, 31 books, at least (?) People borrow the same books.

The first problem is that there are four ways to borrow only one book; there are four * 3 / 2 = six ways to borrow two books. According to the drawer principle, the books borrowed by two people of at least 11 talents are exactly the same
Second, there are four kinds of books, six kinds of books, four kinds of books, four kinds of books, and one kind of books. There are 15 kinds of books. 31 people borrow at least three books

Finding all second order matrices with square equal to [10]
The matrix is 1.0
1 1

The lower triangular matrix can only be the square of the lower triangular matrix
Suppose X=
x 0
y z
X^2=
x^2 0
(x+z)y z^2
X ^ 2 again=
1 0
1 1
So x ^ 2 = Z ^ 2 = 1, (x + Z) y = 1,
The solution is x = 1 or x = - 1, z = 1 or Z = - 1
If x = 1, z = 1, then y = 1 / 2
If x = - 1, z = - 1, then y = - 1 / 2
If x = - 1, z = 1 or x = 1, z = - 1, then y does not exist, so the second order matrix is
1 0
1/2 1
or
-1 0
-1/2 -1

How can each be an appositive of a noun?
for instance

We each have a cellphone ~ each is the appositive of we ~ the meaning of each of us ~ the number of predicate verbs depends on the subject ~ not on the appositive each~
Each of us…… After the subject, the predicate verb is singular