In the following statements about velocity and acceleration, the correct one is () A. Speed is the physical quantity to describe the change speed of the moving object's position, and acceleration is the physical quantity to describe the change speed of the moving object's speed. B. both speed and acceleration are vectors. C. if the acceleration is large, the motion speed is also large, and the change of speed must be large. D. the direction of acceleration is the direction of the object's motion

A. The physical meaning of velocity is to describe the speed of an object's movement, and acceleration is to describe the speed of an object's change. So a is correct. & nbsp; & nbsp; & nbsp; B, velocity and acceleration not only have size, but also have direction. They are vectors. So B is correct. & nbsp; & nbsp; & nbsp; & nbsp; C. If the acceleration is large, the speed of the object changes quickly, but the speed is not necessarily large, and the change of the speed is not necessarily large. So C is wrong

Acceleration is a physical quantity that describes how fast an object changes. In uniform circular motion, the speed of an object is constant and the direction is constantly changing

In the uniform circular motion, the velocity of the object remains the same, but the velocity changes,
Similarly, in uniform circular motion, acceleration is a physical quantity that describes how fast an object's velocity changes
There is acceleration as long as it is not moving in a uniform straight line or at rest

Isn't acceleration a direction of magnitude? How can it only represent the physical quantity of the speed change of an object?

If the direction of acceleration is in a straight line with the direction of velocity, the acceleration only changes the velocity; if the direction of acceleration is perpendicular to the direction of velocity, the acceleration only changes the direction of velocity; if the direction of acceleration is neither perpendicular nor parallel to the direction of velocity, the acceleration changes the direction of velocity as well

Definite integral of SiNx function
In general, after the definite integral is - cosx, the area on [0, pie] is 2
But the average value of a period of sine function can be regarded as (SiNx) max / radical 2
Let me very tangled, so the area should be root 2 * Pie / 2
Then I'm forced to get Pai = 2 root 2. There seems to be a problem,
The above should be [0, Pai], half a cycle, or in terms of | SiNx |

The average value of SiNx is 0

Finding indefinite integral of function y = SiNx / (1 + SiNx)

∫[sinx/(1+sinx)]dx
=∫dx-∫[1/(1+sinx)]dx
=∫dx-∫{1/[1+cos(π/2-x)]}dx
=∫dx-1/2∫{1/[cos(π/4-x/2)]^2}dx
=x+tan(π/4-x/2)+C

Solving indefinite integrals X / sin ^ x, ln (x + radical (1 + x ^ 2), Xe ^ 2x with partial integrals

∫ x/sin²x dx= ∫ xcsc²x dx= ∫ x d(- cotx)= - xcotx + ∫ cotx dx= - xcotx + ∫ d(sinx)/sinx= - xcotx + ln|sinx| + C∫ ln[x + √(1 + x²)] dx= xln[x + √(1 + x²)] - ∫ x * 1/[x + √...

A detailed explanation of the indefinite integral ∫ [ln (SiN x)] / (SiN x) ^ 2 DX

∫ln（sinx）d-cotx=-cotx ·ln（sinx）+∫cotxdln（sinx）=-cotx lnsinx+∫﹙1-sin²x﹚／sin²xdx=-cotx lnsinx-cotx-x+c

The indefinite integral of SiNx square root, that is: ∫ √ sin (x ^ 2) DX detailed solution
Only the result is 0

The original function of indefinite integral is not a specific value,
Moreover, the original function of this indefinite integral can not be expressed by elementary function, only by power series
If it is a definite integral and the integral interval is symmetric, then the result is indeed 0
Because y = √ sin (x ^ 2)
It's an even function
The result of definite integral of even function with respect to symmetric interval is 0

How does the indefinite integral of (1-sin ^ 2 (x)) d (SiN x) = sin X-1 / 3 sin ^ 3 (x) + C change?

The basic formula of integral is: ∫ DX = x + C ∫ dy = y + C ∫ Du = y + C ∫ D (cat and dog) = (cat and dog) + C ∫ xdx = & frac12; X & sup2; + C ∫ VDV = & frac12; X & sup2; + C ∫ D (cat and dog) =

Find the indefinite integral of (SiNx &; cosx) / (1 + sin ^ 4x)

Use the differential method to calculate. The economic mathematics team will help you solve it. Please evaluate it in time