-3x = 0. This is the equation,

-3x = 0. This is the equation,

-3x=0
Divide both sides of the equation by (- 3)
-3x÷(-3)=0÷(-3)
x=0

What is the solution of the equation 5x + 0.45 = 3x + 1.65?

5x+0.45=3x+1.65
5x-3x=1.65-0.45
2x=1.2
x=0.6

50 written division problems for grade 4 of PEP

672÷14= 96÷12= 762÷12= 336÷84= 828÷18= 260÷32= 406÷58= 460÷28= 790÷34= 968÷28= 648÷36= 874÷23= 406÷58= 624÷24= 368÷46= 72÷12= 1752÷30= 897÷27= 864÷47= 962÷35= 576÷18=912÷38=200÷32=360÷24=832÷26=574÷41=936÷39=186÷60=816÷68=492÷24=392÷14=350÷26=762÷13=786÷64=516÷43=666÷18=460÷23=820÷41=560÷28=448÷32=476÷14=912÷38=456÷12=336÷84=672÷42=249÷27=274÷38=701÷91=

The solutions of the equation ex-x-2 = 0 in the range of real numbers are___ One

From ex-x-2 = 0, we can get ex = x + 2, let y = ex, y = x + 2 draw the image of y = ex and y = x + 2 in the same coordinate system, as shown in the figure. From the image, we can see that y = ex and y = x + 2 have two intersections, so the equation ex-x-2 = 0 has two solutions in the range of real number. So the answer is: 2

Given the elliptic equation x ^ 2 / 9 + y ^ 2 / 4 = 1, four vertices of square ABCD are on the ellipse, the area of square ABCD can be obtained

The vertex coordinates (x, y) of the square satisfy the following conditions at the same time:
X ^ 2 / 9 + y ^ 2 / 4 = 1; X ^ 2 = y ^ 2; so x ^ 2 = 36 / 13;
Area of square ABCD = 4 * x ^ 2 = 144 / 13

Calculation of falling off form in grade 4 (with brackets)
Must be a recursive equation, as long as the integer, there must be brackets

158 divided by [(180-120) divided by 30]

If the function f (x) = (2b − 1) x + B − 1, (x > 0) − x2 + (2 − b) x, (x ≤ 0) is an increasing function on (- ∞, + ∞), the value range of real number B is______ ．

∵ function f (x) = (2b − 1) x + B − 1, (x ＞ 0) − x2 + (2 − b) x, (x ≤ 0) is an increasing function on (- ∞, + ∞), and ∵ 2B − 1 ＞ 0b − 1 ≥ 02 − B2 ≥ 0, the solution is 1 ≤ B ≤ 2, so the value range of real number B is [1,2], so the answer is [1,2]

An ellipse and a hyperbola have a common focus, and the sum of eccentricity is 2. The known elliptic equation is 25X ^ 2 + 9y ^ 2 = 1, so we can find the hyperbola

Let the eccentricity of the ellipse be E1, and the hyperbola E2. From the problem, we can see that C is on the Y axis, then a ^ 2 = 1 / 9, B ^ 2 = 1 / 25. So C = 4 / 15. E1 = C / a = 4 / 5. Because E1 + E2 = 2, so E2 = 6 / 5. And two curves have a common focus, so a ^ 2 of the hyperbola = 4 / 81, B ^ 2 = 44 / 2025. Hyperbola x ^ 2 / b ^ 2-y ^ 2 / A ^ 2 = 1

Several simple arithmetic problems in primary school
0.8 X 0.25 + 0.8
0.49 X 10.1
1.25 X 7.5 X 0.8 - 5.6
5.9 X 10 - 5.9 X 3
0.57 X 101 - 0.57
That's all. I hope you can help me I am 5 years old. Some questions are not very good

0.8 X 0.25 + 0.8
=0.8*(0.25+1)
=0.8*1.25
=1
0.49 X 10.1
=0.49*(10+0.1)
=0.49*10+0.49*0.1
=4.9+0.049
=4.949
1.25 X 7.5 X 0.8 - 5.6
=(1.25*0.8)*7.5-5.6
=7.5-5.6
=1.9
5.9 X 10 - 5.9 X 3
=5.9*(10-3)
=5.9*7
=(6-0.1)*7
=42-0.7
=41.3
0.57 X 101 - 0.57
=0.57*(101-1)
=0.57*100
=57

In the derivative section, the domain of function generally refers to the open interval, because there is no increment at the end point

Take the left end point of a closed interval as an example. At this point, because there is no definition on the left side of the end point, there is no increment on the left side, so the left derivative does not exist; on the contrary, the right derivative usually exists
The definition of derivative is that the left derivative exists and the right derivative exists, and they are equal. Therefore, the domain of function derivative is open