Let a be a constant, f (x) = x2-4x + 3. If f (x + a) is an even function, then a=______ ；f（f（a））=______ ．

Let a be a constant, f (x) = x2-4x + 3. If f (x + a) is an even function, then a=______ ；f（f（a））=______ ．

The function f (x + a) is an even function, that is, f (x + a) = f (- x + a). Substituting it into the function formula, we can get 4ax = 8x, a = 2. Then f (a) = f (2) = - 1, f (- 1) = 8, so the answer is 2, 8

On every curve of the image with inverse scale function y = 1 − MX, y decreases with the increase of X, then the value range of M is smaller______ ．

∵ on every curve of the image with inverse scale function y = 1 − MX, y decreases with the increase of X, ∵ 1-m > 0, the solution is m < 1, so the answer is m < 1

When the product is negative, there are odd negative factors
What does this sentence mean? Why?

There are odd negative factors. That is to say, these rational numbers have odd negative numbers
If you multiply odd negative numbers, the product is still negative, and then multiply with other positive numbers, the result is still negative

(x squared - 2XY + y squared divided by X squared + x) × (x + 1 divided by X squared - y squared)

Solution
(x²-2xy+y²)/(x²+x)×(x+1)/(x²-y²)
=(x-y)²/[x(x+1)]×(x+1)/(x+y)(x-y)
=(x-y)/x(x+y)

How to factorize x ^ 3 + 6x ^ 2 + 11x + 6

Let x ^ 3 + 6x ^ 2 + 11x + 6 = (x + a) (x ^ 2 + BX + C) = x ^ 3 + (a + b) x ^ 2 + (AB + C) x + AC, so a + B = 6ab + C = 11ac = 6, A1 = 2 A2 = 3, A3 = 1B1 = 4, B2 = 3, B3 = 5c1 = 3, C2 = 2, C3 = 6. When a = 2B = 4C = 3, x ^ 3 + 6x ^ 2 + 11x + 6 = (x + 2) (x ^ 2 + 4x + 3) = (x + 2) (x + 1) (x + 3)

If the solution set of 1 {x-m} > 3-m is x > 1, then the value of M is

Multiply by three on both sides
x-m>9-3m
x>9-2m
The solution set is x > 1
So 9-2m = 1
m=4

What does bv-450 / 750v-2 * 2.5 PC16 CC WC stand for

Bv: copper core PVC insulated wire 450 / 750V: AC voltage inner core withstand voltage 450V / outer insulation withstand voltage 750v2 * 2.5: two 2.5mm2 wires PC16 CC WC: wire through PC16 (Φ 16 polycarbonate plastic pipe) or CC concealed laying in roof or roof or WC concealed laying in wall

Solving quadratic equation with one variable by factorization (!)
solve equations:
1. The solution of the equation t (T + 3) = 28 is____
2. The roots of (Y-5) (y + 2) = 1____
3. Quarter x-178; + half x-178; - 6 = 0
4、(x-1)²-4(x-1)-21=0
5、y²+7+6=0
6. The solution of (2x + 1) &# 178; + 3 (2x + 1) = 0 is____
7、(x+1)(x+3)=12
8、10x²-x-3=0
9、y²-15=2y
10、(2x-1)(x-1)=1
Will add points. Swearing detour^^

1、t(t+3)=28
t²+3t-28=0
(t-4)(t+7)=0
T = 4 or T = - 7
2、(y-5)(y+2)=1
y²-3y-11=0
This equation can not be solved by factorization
y=(-3±√(3^2-4*1*(-11)))/(2*1)
y=(-3±√53)/2
3、1/4 x²+2/5 x²-6=0
(5+8)/20 x²-6=0
13x²-120=0
x=±(2√390)/13
4、(x-1)²-4(x-1)-21=0
x²-2x+1-4x+4-21=0
x²-6x-16=0
(x-8)(x+2)=0
X = 8 or x = - 2
5、y²+7+6=0
The &; of the equation needs to be greater than zero, but the &; of the secondary equation is less than zero, so there is no solution
6、(2x+1)²+3(2x+1)=0
4x²+4x+1+6x+3=0
4x²+10x+4=0
(x+2)(4x+2)=0
X = - 2 or x = - 1 / 2
7、(x+1)(x+3)=12
x²+4x+3-12=0
x²+4x-9=0
x=(-4±√(4^2-4*1*(-9)))/(2*1)
x=-2±√13
8、10x²-x-3=0
(2x+1)(5x-3)=0
X = - 1 / 2 or x = 3 / 5
9、y²-15=2y
y²-15-2y=0
(y+3)(y-5)=0
Y = - 3 or y = 5
10、(2x-1)(x-1)=1
2x²-3x+1-1=0
2x²-3x=0
x(2x-3)=0
X = 0 or x = 3 / 2
Some problems can't be solved by factoring. I'm sorry! But I can't solve them by factoring. I use the method of finding the root formula... The answer is right~

How to find the sum of binomial coefficients
Such as the title

It is very important to write the formula correctly when learning binomial
(1) Binomial theorem
(a+b)n=cn0an+cn1an-1b+… +cnran-rbr+… +Cnnbn (the display here has a way out, I believe you can understand), where r = 0,1,2 ,n,n∈N.
The general term of the expansion is as follows:
Tr+1=cnran-rbr(r=0,1,… n),
The binomial remainder of the expansion is CNR (r = 0,1,...) n)
(2) Properties of binomial remainder
① In the binomial expansion, the remainder of the binomial which is equidistant from the beginning and the end is equal, that is, CNR = cnn-r (r = 0,1,2,...) n) (2) from CNR ≥ cnr-1
cnr≥cn+1r
The results show that (n-1) / 2 ≤ R ≤ (n + 1) / 2
When n is even, the central term of the expansion is TN / 2 + 1, and the remainder of the binomial is the largest;
When n is odd, the middle two terms of the expansion are t (n + 1) / 2 + 1 and t (n + 1) / 2 + 1, and the coefficient of the binomial is CN (n-1) / 2 (or CN (n + 1) / 2)
It is the largest
③ The relationship between two binomial coefficients: CNR + 1 = (n + R) / (R + 1) CNR (R ≤ n, n ∈ n, R ∈)
④ The sum of all binomial coefficients of binomial expansion: cN0 + cN1 + cn2 + +cnn＝Zn,
⑤ In binomial expansion, the sum of binomial coefficients of odd term is equal to the sum of binomial coefficients of even term
cn0+cn2+cn4+… ＝cn1+cn31+cn5+… ＝2n-1

Given a + B = 3, ab = 1, then the value of a of B + B of a is

B of a + a of B = (a ^ 2 + B ^ 2) / AB = [(a + b) ^ 2-2ab] / AB = (9-2) / 1 = 7 team born for dream^_ ^I wish you progress in your study! If you agree with my answer, please click the "adopt as satisfied answer" button in time ~ the mobile phone questioner can click "satisfied" in the upper right corner of the client