Y ′ = 10 ^ (x + y) to find the general solution of the differential equation

dy/dx=10^x* 10^y
10^(-y)dy=10^x dx
Integral: - 10 ^ (- y) / ln10 = 10 ^ X / ln10 + C1
Simplify y = - LG (C-10 ^ x)

General solution of total differential y '' + 2Y '+ y = cos x

∵ the characteristic equation of the homogeneous equation y '' + 2Y '+ y = 0 is R & # 178; + 2R + 1 = 0, then r = - 1 ∵ the general solution of the homogeneous equation is y = (c1x + C2) e ^ (- x) (C1, C2 are integral constants) ∵ let the solution of the original equation be y = acosx + bsinx and substitute it into the original equation, then 2acosx-2bsinx = cosx = > 2A = 1, - 2b = 0 = = = > A = 1 / 2, B = 0 ∵

In the parallel circuit, the fixed value resistor and the bulb are connected respectively. The voltmeter measures the power supply voltage, and the ammeter measures the bulb. The power supply voltage does not change. The switch controls the resistor switch to close
What is the change of voltage, current and bulb brightness

The power supply resistance is not considered
1. The initial state is that the switch is closed. When the switch is off, the voltmeter does not change, the ammeter increases and the bulb turns on
2. The initial state is switch off. When the switch is closed, the voltmeter will not change, the ammeter will decrease and the bulb will be dark
Cause: parallel circuit shunt voltage, light by power P = UV determine

8x + 0.4 × 9 = 6 solved by equation

8x+0.4×9=6
8x=6-3.6
x=2.4/8
x=0.3

An ammeter, its full-scale current is ia = 100ua, internal resistance RA = 1K ohm. If it is changed to a 10mA ammeter, how much resistance RB should be paralleled?

127 problems in solving linear equation of one variable
Help me find 127 questions without answers

7(2x-1)-3(4x-1)=4(3x+2)-1;
(5y+1)+ (1-y)= (9y+1)+ (1-3y);
20%+(1-20%)(320-x)=320×40%
2(x-2)+2=x+1
2(x-2)-3(4x-1)=9(1-x)
x/3 -5 = (5-x)/2
2(x+1) /3=5(x+1) /6 -1
(1/5)x +1 =(2x+1)/4
(5-2)/2 - (4+x)/3 =1
x/3 -1 = (1-x)/2
(x-2)/2 - (3x-2)/4 =-1
11x+64-2x=100-9x
15-(8-5x)=7x+(4-3x)
3(x-7)-2[9-4(2-x)]=22
3/2[2/3(1/4x-1)-2]-x=2
2(x-2)-3(4x-1)=9(1-x)
11x+64-2x=100-9x
15-(8-5x)=7x+(4-3x)
3(x-7)-2[9-4(2-x)]=22
3/2[2/3(1/4x-1)-2]-x=2
2(x-2)+2=x+1
1.7(2x-1)-3(4x-1)=4(3x+2)-1
2.(5y+1)+ (1-y)= (9y+1)+ (1-3y)
3.[ (- 2)-4 ]=x+2
4.20%+(1-20%)(320-x)=320×40%
5.2(x-2)+2=x+1
6.2(x-2)-3(4x-1)=9(1-x)
7.11x+64-2x=100-9x
8.15-(8-5x)=7x+(4-3x)
9.3(x-7)-2[9-4(2-x)]=22
10.3/2[2/3(1/4x-1)-2]-x=2
11.5x+1-2x=3x-2
12.3y-4=2y+1
13.87X*13=5
14.7Z/93=41
15.15X+863-65X=54
16.58Y*55=27489
17.2（x+2）+4=9
18.2(x+4)=10
19.3(x-5)=18
20.4x+8=2(x-1)
21.3(x+3)=9+x
22.6(x/2+1)=12
23.9(x+6)=63
24.2+x=2(x-1/2)
25.8x+3(1-x)=-2
26.7+x-2(x-1)=1
27.x/3 -5 = (5-x)/2
28.2(x+1) /3=5(x+1) /6 -1
29.(1/5)x +1 =(2x+1)/4
30.(5-2)/2 - (4+x)/3 =1
15x-8(5x+1.5)=18*1.25+x
3X+189=521
4Y+119=22
3X*189=5
8Z/6=458
3X+77=59
4Y-6985=81
87X*13=5
7Z/93=41
15X+863-65X=54
58Y*55=27489
1.2(x-2)-3(4x-1)=9(1-x)
2.11x+64-2x=100-9x
3.15-(8-5x)=7x+(4-3x)
4.3(x-7)-2[9-4(2-x)]=22
5.3/2[2/3(1/4x-1)-2]-x=2
6.2(x-2)+2=x+1
7.0.4(x-0.2)+1.5=0.7x-0.38
8.30x-10(10-x)=100
9.4(x+2)=5(x-2)
10.120-4(x+5)=25
11.15x+863-65x=54
12.12.3(x-2)+1=x-(2x-1)
13.11x+64-2x=100-9x
14.14.59+x-25.31=0
15.x-48.32+78.51=80
16.820-16x=45.5×8
17.(x-6)×7=2x
18.3x+x=18
19.0.8+3.2=7.2
20.12.5-3x=6.5
21.1.2(x-0.64)=0.54
22.x+12.5=3.5x
23.8x-22.8=1.2
24.1\ 50x+10=60
25.2\ 60x-30=20
26.3\ 3^20x+50=110
27.4\ 2x=5x-3
28.5\ 90=10+x
29.6\ 90+20x=30
30.7\ 691+3x=700
1 2x-10.3x=15
2 0.52x-(1-0.52)x=80
3 x/2+3x/2=7
4 3x+7=32-2x
5 3x+5(138-x)=540
6 3x-7(x-1)=3-2(x+3)
7 18x+3x-3=18-2(2x-1)
8 3(20-y)=6y-4(y-11)
9 -(x/4-1)=5
10 3[4(5y-1)-8]=6
3X+5X=48 14X-8X=12 6*5+2X=44
20X-50=50 28+6X=88 32-22X=10
24-3X=3 10X*（5+1）=60 99X=100-X
X+3=18 X-6=12 56-2X=20
4y+2=6 x+32=76 3x+6=18
16+8x=40 2x-8=8 4x-3*9=29
8x-3x=105 x-6*5=42 x+5=7
2x+3=10 12x-9x=9 6x+18=48
56x-50x=30 5x=15 78-5x=28
32y-29=3 5x+5=15 89x-9=80
100-20x=20 55x-25x=60 76y-75=1
23y-23=23 4x-20=0 80y+20=100
53x-90=16 2x+9x=11 12y-12=24
80+5x=100 7x-8=6 65x+35=100
19y+y=40 25-5x=15 79y+y=80
42x+28x=140 3x-1=8 90y-90=90
80y-90=70 78y+2y=160 88-x=80
9-4x=1 20x=40 65y-30=100
51y-y=100 85y+1=-86 45x-50=40
3X+18=52 x=34/3
4Y+11=22 y=11/4
3X*9=5 x=5/27
8Z/6=48 z=36
3X+7=59 x=52/3
4Y-69=81 y=75/4
8X*6=5 x=5/48
7Z/9=4 y=63/7
15X+8-5X=54 x=4.6
5Y*5=27 y=27/40
8x+2=10 x=1
x*8=88 x=11
y-90=1 y=91
2x-98=2 x=50
6x*6=12 x=1/3
5-6=5x x=-1/5
6*x=42 x=7
55-y=33 y=22
11*3x=60 x=20/11
8-y=2 y=-6
1.x+2=3
2.x+32=33
3.x+6=18
4.4+x=47
5.19-x=8
6.98-x=13
7.66-x=10
8.5x=10
9.3x=27
10.7x=7
11.8x=8
12.9x=9
13.10x=100
14.66x=660
15.7x=49
16.2x=4
17.3x=9
18.4x=16
19.5x=25
20.6x=36
21.8x=64
22.9x=81
23.10x=100
24.11x=121
25.12x=144
26.13x=169
27.14x=196
28.15x=225
29.16x=256
30.17x=289
31.18x=324
32.19x=361
33.20x=400
31.21x=441
32.22x=484
33.111x=12321
34.1111x=1234321
35.11111x=123454321
36.111111x=12345654321
37.46/x=23
38.64/x=8
39.99/x=11
40.1235467564x=0
41.2x+1= -2+x
42.4x-3(20-x)=3
43.．-2(x-1)=4
44.3X+189=521
45.4Y+119=22 5
46.3X+77=59
47.4Y-6985=81
48.X=0.1
49.5X=55.5
0.Y=50-85

Household appliances investigate the four names of household appliances and the work they can do, the form of input energy (electric energy) and the form of output energy

Electric fan ----- input energy, electric energy; function: blowing and cooling, output energy: wind energy. Juice machine ----- input energy, electric energy; function: juice making, output energy: mechanical energy. Heater ----- input energy, electric energy; function: heating, heating, output energy: heat energy. Washing machine ----- input energy

150-120 divided by 1.4 × 0.84
Simple calculation of 17 and 2 / 5 × 37-174 × 1.9 + 17 and 2 / 5 × 82
1999 and 1991 / 1999 × 1 / 4-1997 / 1999

(150-120)/1.4x0.84
=150/1.4x0.84-120/1.4x0.84
=25/1.4x0.14-20/1.4x0.14
=(25-20)/1.4x0.14
=5/0.196
=500/196
=125/49
17 and 2 / 5 × 37-174 × 1.9 + 17 and 2 / 5 × 82
=87 / 5x37-174x19 / 10 + 17 and 2 / 5 × 82
=87/5(37-19+82)
=87/5x100
=184
1999 and 1991 / 1999 × 1 / 4-1997 / 1999
=｛［(2000-1)²+(2000-9)］/(2000-1)｝1/4-（2000-3)/(2000-1)
=［(4000000-4000+1+2000-9)/(2000-1)］1/4-（2000-3)/(2000-1)
=(1000000-1000+500-2-2000+3)/(2000-1)
=997501/1999
=499

The problem of changing 48V to 60V for electric vehicle
Will the change of 48V to 60V affect 350W motor and 350W controller,
How much speed can the electric vehicle increase if the 48V is changed to 60V? Will the starting strength increase?

I'm the quality inspector of the tram factory. I personally changed it. There's no problem with the 350W motor and the 350W controller, but the controller must be 60V, 350-450w, otherwise it will burn the components in the controller. If the controller uses more than 900W, it will burn the motor. The charger should also be changed to 60V, and the lights and instruments should be changed

5 × 7 / 13 and 4 × 14 / 13 can be calculated simply

5 out of 13 × 4 out of 7 × 14 = 4 out of 7 × 14 * 5 / 13 = 8 * 5 / 13 = 40 / 13

Y ′ = 10 ^ (x + y) to find the general solution of the differential equation