There are two points m.n on the line ab. point m divides line AB into two parts 2:3, and point n divides line AB into two parts 2:1, and Mn = 2cm

There are two points m.n on the line ab. point m divides line AB into two parts 2:3, and point n divides line AB into two parts 2:1, and Mn = 2cm

Line AB is divided into 15 equal parts, and each part is X,
Point m divides line AB into 2:3 parts, am = 6x, MB = 9x
Point n divides line AB into two parts, an = 10x, Nb = 5x
AN-AM=MN
10X-6X=2
X=1/2
AB=15X=15/2

It is known that there are two points m and N on the line ab. point m divides AB into two parts 2:3 and point n divides AB into two parts 4:1. If Mn = 3cm, the length of AM and Nb can be obtained

∵ point m divides AB into 2:3 parts, ∵ am = 25ab; ∵ point n divides AB into 4:1 parts, ∵ an-am = Mn, ∵ 45ab-25ab = 3, ∵ AB = 7.5cm, ∵ am = 25ab = 3cm. ∵ NB = ab-an = 15ab = 1.5cm. So am = 3cm, Nb = 1.5cm

When two resistors R1 and R2 are connected in parallel, the total resistance is 4 Ω. When they are connected into the circuit, their current I1: I2 = 1:2, then the resistance values of R1 and R2 are ()
A. 1Ω，3ΩB. 2.7Ω，1.3ΩC. 6Ω，12ΩD. 12Ω，6Ω

∵ two resistors are in parallel, the total resistance in the circuit is r = r1r2r1 + R2 = 4 Ω --- ①∵ the voltage at both ends of each branch in the parallel circuit is equal, ∵ according to u = IR, R1: R2 = I2: I1 = 2:1 --- ② from formula ① and ②, R1 = 12 Ω, R2 = 6 Ω. So D is selected

Simple algorithm of 0.8 times 12.5 + 1.25 + 125

0.8×（12.5+1.25+125）
=0.8×12.5+0.8×1.25+0.8×125
=10+1+100
=111

As shown in the figure, there is a sensitive ammeter with full bias current Ig = 1mA and internal resistance Rg = 10. It is refitted into a voltmeter with 3V and 15V ranges
What is the resistance of R1 and R2?

20
thirty

(1) - 4.8 7 - (+ 4.4 1) - (- 5.2 1) + (- 3.8 1)

(1) - 4 and 8 / 7 - (+ 4 and 4 / 1) - (- 5 and 2 / 1) + (- 3 and 8 / 1) = - 4 - 7 / 8 - 4 - 1 / 4 + 5 + 1 / 2 - 3 - 1 / 8 = - 4 - 4 - 3 + 5 - 1 / 4 + 1 / 2 - (1 / 8 + 7 / 8) = - 6 + 1 / 4 - 1 = - 7 + 1 / 4 = - 6 and 4 / 3 donor, I see your bones are clear

English writing of common mathematical symbols
How to write + - * / mainly. For example, + is sum

+：sum (plus,add)
-:sub
*:mul(multiple)
/:div(division)

Difficulties in life
emergency

Conversion relationship between power (kw) and kilowatt hour (KVH)
It's better to have a unified form!
I'm sorry! dial the wrong number! It's the conversion of power to kilovolt ampere

There's something wrong with your question
Kilowatt city is the unit of electric energy. How can it be converted to the unit of electric power?
But there are others
1kW = 1000W (both W and kW are electrical power units)
1kW = 3.6 * 10 ^ 6 joules (note that joules are also electric energy units)
If there is any relationship between them, it is
1W*1S=1J
When 1kW * 1H = 1kW, 1kwh is equivalent to the electric energy consumed by a 1kW electric appliance in one hour

If the area of a rectangle is 3a2-3ab + 6a and one side is 3a, its perimeter is______ ．

Its perimeter is: 2 [(3a2-3ab + 6a) △ 3A + 3A] = 2 (a-b + 2 + 3a), = 2 (4a-b + 2), = 8a-2b + 4