Analytic expression of quadratic function y = - x square + 2x Like the title,

Analytic expression of quadratic function y = - x square + 2x Like the title,

I don't understand the meaning of the landlord
Y = - X & # 178; + 2x is an analytic expression of quadratic function

In the formula y = 2x square + 3bx + C, when x = 1, y = 12; when x = negative 2, y = negative 9

x=1,y=12
x=-2,y=-9
therefore
12=2+3b+c (1)
-9=8-6b+c (2)
(1)-(2)
21=-6+9b
b=3
c=12-2-3b=1

The density p of carbon dioxide is known, and the analytic formula of the function of volume V is p = 9.9/v
(2) Write the change of density p of carbon dioxide with the increase of volume v

The density p of carbon dioxide decreases with the increase of volume V, which is an inverse proportional function

If 2 + 2 / 3 = 2 square times 2 / 3, if 10 + A / b = 10 square times a / B, (a, B are positive integers), find the value of a + B
Please!

According to the known conditions, 2 + 2 / 3 = 2 ^ 2 × (2 / 3), 3 + 3 / 8 = 3 ^ 2 × (3 / 8), 4 + 4 / 15 = 4 ^ 2 × (4 / 15), and can be regarded as 2 / 3 = 2 / (2 ^ 2-1), 3 / 8 = 3 / (3 ^ 2-1), 4 / 15 = 4 / (4 ^ 2-1) 10 + A / b = 10 + 10 / (10 ^ 2-1), that is, 10 + 10 / 99. If this assumption is true, 10 + A / b = 10 + 10 / 99 should be equal to 1000

The standard equation of parabola with quasilinear equation x = 2 is______ ．

Let the parabola y2 = MX, then − M4 = 2, ｜ M = - 8, the standard equation of the parabola is y2 = - 8x, so the answer is y2 = - 8x

When the engine cylinder pressure is low, the content of () will increase
A co B HC C NOx D Co and HC

d

Sum Rule
What law does 32 * 5 + 68 * 5 use? Our teacher said that we used the law of combination of multiplication, which is to combine 32 and 68, but the law of combination of multiplication is not, Is (a * b) * C = a * (b * c)? The law of combination of multiplication should be multiplication! And the law of distribution of multiplication should be (a + b) * C = a * C + b * C? This formula should restore the formula after distribution. What kind of law is used? I think the law of distribution of multiplication is used!

Multiplicative allocation rate, (a + b) * C = a * C + b * C, 32 * 5 + 68 * 5 = (32 + 68) * 5 = 100 * 5 = 500

General solution of dy / DX = y + 1

Rewrite as
d(y+1)/(y+1)=dx
Integral gain
ln(y+1)=x+C1
y+1=Ce^x
y=Ce^x-1
C is the integral constant

How to convert cubic meter and liter

1 liter (L) = 1 cubic decimeter = 1 / 1000 cubic meter, 1 cubic meter = 1000 liter

Using multiplication formula to calculate (≥ ▽≤)/~
Given that A-B = 2, B-C = 3, find the value of a & # 710; 2 + B & # 710; 2 + C & # 710; 2-ab-bc-ac (the preceding is the square of a + the square of B + the square of C),

(a-b) ^ 2 = a ^ 2-2ab + B ^ 2 = 4; 1 (B-C) ^ 2 = B ^ 2-2bc + C ^ 2 = 9; 2a-b = 2, B-C = 3, we can know a-c = 5; (A-C) ^ 2 = a ^ 2-2ac + C ^ 2 = 25; 3 add 1,2,3 to get: 2 (A & # 710; 2 + B & # 710; 2 + C & # 710; 2-AB BC AC) = 4 + 9 + 25 = 38; we can know a & # 710; 2 + B & # 710; 2 +