Primitive function of general logarithmic function (indefinite integral)

Primitive function of general logarithmic function (indefinite integral)

∫lnxdx
=xlnx-∫xd(lnx)
=xlnx-∫(x*1/x)dx
=xlnx-∫dx
=xlnx-x+C
∫㏒ B (x) DX, with the base as the logarithm of B
=∫(lnx/lnb)dx
=(1/lnb)∫lnxdx
=(1/lnb)(xlnx-x)+C
=(xlnx-x)/lnb+C

There are some questions about the concept of indefinite integral primitive function. Can you give some examples;

For example, if we derive 2x from X, then the original function of 2x is x + C, because when we want to consider the constant derivative = 0, we ignore it
For example, if we get cosx by deriving SiNx, then the original function of cosx is SiNx + C

If a + B = 2, (1-A) & # / B + (1-B) & # / a = - 4, then ab=

(1-a-a-a-h-178; (B + (1-b-b) at the same time, the two sides of the same time multiply AB (a (1-A) - 178; (b (1-B) - 178; (b (1-B) - 178; (b (1-B) - 178; (b (1-B) - 178; (B (1-B) - 178; (b (1-B) - 178; (b (1-B) - 178; (b (1-B) - a-2a-a-a-2a-178; (b-b-2b-2b-2b-178; (; (b-2b-2b-2b) 178; + B \\\\\\\\\\\\\\\\\\\\\\\\- 4AB  2-2 [(a + b) & #178; - 2Ab] + (a + B)

Factorization of a ^ 2-9

a^2-9＝a^2-3^2=(a+3)(a-3)

The store has a new batch of fruits. Pears are 40% more than apples and oranges are 20% less than apples

360 ÷ (1-20%) = 450 (kg) Apple
450 * (1 + 40%) = 630 (kg) Pear

It is known that the bivariate linear equation PX + 2Y = 8, 5x-6y = 4, 2x + 5y-8 = 0 has a common solution

By solving the equations 5x − 6y = 42x + 5Y − 8 = 0, we can get x = 6837y = 3237. By substituting PX + 2Y = 8, we can get 6837p + 2 × 3237 = 8 and P = 5817

How many kg / m3 is 13.6 g / cm3?

13.6 * 10

A fruit wholesale market brought in a batch of apples, sold 400 boxes in the first day, sold 2 / 7 of the total in the second day, sold 1 / 5 more in the second day than in the first day
In a fruit wholesale market, a batch of apples are transported in. 400 boxes are sold in the first day, 2 / 7 of the total number are sold in the second day, and 1 / 5 more are sold in the second day than in the first day. How many boxes of apples are transported in? (no equation)

2 / 7 of the total sold on the first day (1 + 1 / 5) = 5 / 21
Therefore, the total number of imported apples is 400 △ 5 / 21 = 1680 cases
Have a good time

Half, two-thirds, three-quarters Ninety nine percent. What's the product of these ninety-nine fractions
Half, two-thirds, three-quarters Ninety nine percent. What's the product of these ninety-nine fractions

2 and 2
3 and 3
Keep going
Only 1 and 100
So 1 / 100

21. In a single-phase sinusoidal AC circuit, if the resistance and reactance are equal, what is the phase difference between the current and voltage in the circuit?
A、π/4 B、π/3 C、π/2 D、π

Building owner,
The voltage of the inductor is 90 degrees ahead of the current,
The voltage phase of the capacitor lags the current by 90 degrees
The voltage of the resistor is synchronized with the phase of the current
So the above questions should be: C
Before analog electronic circuit technology still remember so much, hope to be useful to you