1. The inductance coil with L = 100mh is connected to the sinusoidal AC power supply with frequency of 50 Hz and 220 V (the resistance is ignored), and the inductive reactance, current and reactive power are calculated [to be specific] 2. A 100 μ f capacitor is connected to a sinusoidal AC power supply of 50 Hz and 220 V (the circuit resistance is ignored), Calculate capacitive reactance, current and reactive power [to be specific]

1. The inductance coil with L = 100mh is connected to the sinusoidal AC power supply with frequency of 50 Hz and 220 V (the resistance is ignored), and the inductive reactance, current and reactive power are calculated [to be specific] 2. A 100 μ f capacitor is connected to a sinusoidal AC power supply of 50 Hz and 220 V (the circuit resistance is ignored), Calculate capacitive reactance, current and reactive power [to be specific]

Inductive reactance is equal to angular velocity times inductance, so 314 times 0.1 equals 31.4 ohm, the current is 220 divided by 31.4 (this is the effective value), and the phase lags by half π. Reactive power equals 220 times the effective value of current
I don't care about the specific data

In a sinusoidal AC circuit with pure inductors, l = 100 MH, f = 50 Hz, (1) given I (T) = 7 sin ω TA, the voltage UL can be obtained

uL = 2 * π * f * L* i (t)
= 220 sin（ωt+π/2）V

In the sinusoidal AC circuit with pure inductive elements, l = 100mh, f = 50Hz, (1) given I (T) = 7 sin ω TA, the voltage UL can be obtained. (2) the circuit with inductive elements can be obtained

1. UL = L * di (I) / DT, 2 is wrong

Is the power factor of RLC series circuit necessarily less than 1

Not necessarily
When working at the resonant frequency (excitation signal frequency is equal to the natural frequency of the circuit), the values of inductive reactance and capacitive reactance are equal, the circuit is pure resistive, and the power factor is equal to 1

If x is greater than or equal to a plus 1 and X is less than or equal to 2A minus 1, then
If x is greater than or equal to a plus 1
If x is less than or equal to 2A minus 1, then a has a solution
A greater than 2 a greater than or equal to 2 a less than or equal to 2 a less than 2

{x≥a+1
{x≤2a-1
==>
a+1≤x≤2a-1
a+1≤2a-1
a≥2
Select [b]

99 times 99 and 98 out of 99

99 × 99 and 98 / 99
＝99×﹙100－1/99﹚
＝99×100－99×1/99
＝9900－1
＝9899

In the identity (1 + x) ^ n = A0 + a1x + a2x ^ 2 + +In anx ^ n (n is even), A0 + A1 + A2 + +an=?
The original formula has been obtained = CN (0) + CN (1) + CN (2) + +CN (n) [cn (4) is the combination of N and 4, and the symbol will not be typed], and then how to reduce it to 2 ^ (n-1)

In binomial theorem, all binomial coefficients are even = 2 ^ n, odd = 2 ^ n-1, or the element X is assigned to 1

7x of 48 - (1x + 9 of 12) = 15 and 4x + 3 (x + 9) = 97
the sooner the better

7x of 48 - (1x of 12 + 9) = 15
7/48x-1/12x-9=15
1/16x=24
x=384
4X+3（X+9）=97
4x+3x+27=97
7x=70
x=10

A barrel of oil weighs 52.4 kg. After half of the oil is poured out, the barrel weighs 32.8 kg. How many kg does the oil weigh?

52.4-32.8=19.6
Oil weight 19.6 + 19.6 = 39.2

How to judge whether a function is differentiable? For example, the piecewise function y = x * 2 (x is not equal to 3), 0 (x = 3), which is theoretically not differentiable, but can be solved by definition
Can anyone make it clear that there is a discontinuity at x = 3,

Indeed