If the function f (x) = KX ^ 2 + (k-1) x + 3 is a decreasing function in the interval [2,10], find the value range of real number K______

If the function f (x) = KX ^ 2 + (k-1) x + 3 is a decreasing function in the interval [2,10], find the value range of real number K______

A:
The function f (x) = KX ^ 2 + (k-1) x + 3 is a decreasing function in the interval [2,10]
1) When k = 0, f (x) = - x + 3
2）k=21
0

How to prove that a number divided by another number is equal to multiplying its reciprocal

Let a ≠ 0, let B be the reciprocal of a, then AB = 1, that is, B = 1 / A, then C △ a = C / a = C × (1 / a), and 1 / A is the reciprocal of A

The number of terms of polynomial 8x to the fourth power - 2x to the third power - x + 10 is (), the degree is (), the constant term is (), and the highest order term is（

The number of items is four
The number of times is four
The constant term is + 10
The highest power is the fourth power of 8x

Calculation formula of cooling and heating load of air conditioning

1. Cooling load calculation (1) the cooling load calculation of external wall is the cooling load formed by the heat gain of wall and ceiling, which can be calculated by the following formula: Clq τ = KF ⊿ t τ - ε W, where k is the heat transfer coefficient of enclosure structure, w / m2 & # 8226; K; F is the area of wall, m2; β -

The square of (M + n) + |m | = m, |2m-n-2 | = 0, find the value of Mn

Square of (M + n) + | m | = square of M (M + n) > = 0 | m | > = 0
We can see that M > 0 and M + n = 0
|2m-n-2 | = 0 leads to 2m-n = 2
m+n=0
2m-n=2
The solution is m = 2 / 3, n = - 2 / 3
So Mn = - 4 / 9

What's the result of 12 one-third minus 9 / 4 divided by 27 / 2?

Original formula = 12 * 1 / 3-9 / 4 * 2 / 27
=4-1/6
=24/6-1/6
=23/6

If x ^ 2-kx + 25 is a complete square, then the value of K is plus or minus 10. Why

If we know that this problem is a complete square, then it must be (x + C) square or (x-C) square. Obviously, when we square them, we will have C ∧ 2 = 25, so C = 5. In this way, we can substitute C = 5 into two complete square expressions, and we can get k = 10 or K = - 10

How to do 2600 △ 52 simple operation?

2600÷52
=2600÷26÷2
=100÷2
=50

Find the value of X in the following formulas: (1) x & # 179; = 0.008 (2) x & # 179; - 3 = 3 / 8 (3) (x-1) &# 179; = 64

（1）X³=0.008
x=0.2
(2) X & # 179; - 3 = 3 / 8
X & # 179; = 27 / 8
X = 3 / 2
（3）（X-1）³=64
x-1=4
x=5

8km-5km 60m 4 yuan 8 Jiao 2 Fen - 3 yuan 5 jiao 2t9kg + 450kg
To calculate the above problem with decimals,

1)
5km60m=5.06km
8km-5km60m=8km-5.06km=2.94km
2)
4 yuan, 8 Jiao, 2 fen = 4.82 yuan, 3 yuan, 5 jiao = 3.5 yuan
4 yuan 8 Jiao 2 Fen - 3 yuan 5 jiao = 4.82 yuan - 3.5 yuan = 1.32 yuan
3)
2t9kg=2.009t 450kg=0.45t
2t9kg+450kg=2.009t+0.45t=2.459t