If the polynomial - 5x & # 179; - (M + 2) x & # 178; + (3-N) X-1 about X does not contain quadratic term and linear term, the value of M & # 8319; is obtained

If the polynomial - 5x & # 179; - (M + 2) x & # 178; + (3-N) X-1 about X does not contain quadratic term and linear term, the value of M & # 8319; is obtained

According to the meaning of the title
-(m+2)=0
3-n=0
m=-2
n=3
m^n=(-2)^3=-8

Known x ^ M-1

When M-1 > 0, then x < 1, then the positive integer solution is 0,1
When M-1 ＜ 0, then x ＞ 1, then there are infinitely many positive integer solutions of X, that is, 2, 3, 4

To solve the inequality, let the quadratic plus 4x minus 5 of - X be less than 0, and let the quadratic plus 4x minus 5 of - x = 0, B squared - 4ac = 16-20 = - 4 be less than 0, so the inequality has no solution
Is that right?

No
First of all, we need to make X & sup2; coefficient positive
So take - 1 on both sides
x²-4x+5>0
If the discriminant is less than 0, then x & sup2; - 4x + 5 > 0 holds
So x takes any real number

If 10 tons of coal is used, 1 / 5 of the total amount will be used, and () tons of this pile of coal will be left. If 3 tons of coal are used, then () tons of this pile of coal will be left
A natural number () of coal heap is either odd or even, or composite or prime. If the unit of fraction is large, the value of fraction is not necessarily large

If 10 tons of coal is used, 1 / 5 of the total amount will be used, and 4 / 5 of the coal will be left. If 1 / 5 of the coal is used, 9.8 tons will be left. If 3 tons are used, 3 / 10 of the coal will be used
A natural number is either odd or even, or composite or prime
Two scores, the score unit is big, the score value is not necessarily big, right

How to learn the mean inequality? How to use the formula of mean inequality?

1. Harmonic mean: HN = n / (1 / A1 + 1 / A2 +... + 1 / an) 2, geometric mean: GN = (A1A2... An) ^ (1 / N) 3, arithmetic mean: an = (a1 + A2 +... + an) / N 4, square mean: QN = √ (A1 ^ 2 + A2 ^ 2 +... + an ^ 2) / n these four means satisfy the formula of HN ≤ GN ≤ an ≤ QN, that is

Party A and Party B transport goods by two vehicles. Party A transports goods five times and Party B transports goods eight times. Party A transports 4 pieces more each time than Party B, and Party A transports 13 pieces less than Party B at the end. How many pieces does Party B transport each time?

（13+4×5)÷（8-5）=11
B 11 pieces per shipment

Problems of equations and inequalities in senior one mathematics
1. Find the value range of the real number k so that the equation x square + 2 (k-1) x + 2K + 6 = 0
(1) There are two real roots, one larger than 2 and the other smaller than 2;
(2) There are two real roots, both larger than 1;
(3) There are two real roots x1, X2, and satisfy 0
3. Given the set a = {x ^ 2 + 3x + 2 ≥ 0}, set B = {x MX ^ 2-4x + M-1 > 0}, if the intersection of a and B is equal to the empty set, find the value range of real number M.
Classmate, don't you use the last line?

1, (1) Δ = [2 (k-1)] ^ 2-4 (2k + 6) > 0, let two x1, X2, have X1 + x2 = 2-2k, x1x2 = 2K + 6, two real roots, one larger than 2, one smaller than 2, have
（x1-2）（x2-2）

A and B start from AB and meet in 6 hours. A is 15 kilometers slower than B. It is known that the speed ratio of the two cars is 4:5. How many kilometers is ab

Two cars an hour 15 ÷ (5-4) x (5 + 4) = 135 km
Distance 135x6 = 810km
If you don't understand this question, you can ask,

(2010. Zhengzhou three module) known vector a = (3, 4), B = (2, 1), if vector a+xb is perpendicular to B, then the value of X is ().
A. 233B. 323C. 2D. −25

∵ a = (3,4), B = (2, − 1) ∵ a + XB = (3 + 2x, 4-x), − B = (- 2,1) and ∵ a + XB is perpendicular to − B ∵ (3 + 2x) · (- 2) + (4-x) × 1 = 0, the solution is x = − 25, so D is selected

There are four apples of the same weight in the fruit shop. If each apple sells 57 kg, the total kilogram of the remaining apples is equal to the weight of the original basket
How many kilos does the apple basket weigh

57÷（1-1/4）
=57÷3/4
=76kg