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A company's opening inventory in April 2014 was 2,000 pieces, and the unit cost was 3 yuan, and the company's purchase and sale of the inventory in April was shown in the following table: April 3: the number of purchases was 0, and the number of sales was 600 pieces on April 9:

The number of purchases is 1000 pieces, the unit cost is 4 yuan, and the number of sales is 0 April 15: the number of purchases is 0, the number of sales is 1500 pieces April 18: the number of purchases is 3500 pieces, the unit cost is yuan, and the number of sales is 0 April 27:

The number of purchases was 0, and the number of sales was 2,200 piecesAccording to the above data, the first-in-first-out method, the last-in-first-out method and the weighted average method were used to calculate the cost of goods sold and the value of inventory at the end of the period based on the regular inventory system. And: In terms of the three methods of first-in-first-out, last-in-last-out method and weighted average method, in order to reduce the amount of income tax payable in the current period to a minimum, which inventory valuation method do you choose?

Why?

Solution (2): Let the coordinates of the point d (xd, yd) then (0 perpendicular to the y axis through d, de perpendicular to the y axis, connect db, in the trapezoidal deob, you will find that no matter what(yd<-4 or yd>-4).

The area of the triangle BCD = xd * (-yd) + 1 2 * (4-xd) * (yd) + 1 2 * (4 + yd) * xd - 1 2 * ob*oc

xd*yd2yd+1/2*xd*yd

2xd+1/2*xd*yd

2yd+2xd-8

So the area of the triangle bcd = -2xd 2 + 6xd + 8 + 2xd - 8-2xd 2 + 8xd

2(xd-2) 2+8 (recipe).

So when xd=2, the area of the triangle bcd has a maximum value (max=8)yd=xd 2-3xd-4=2 2-3*2-4=-6, so the coordinate of point d is (2,-6).

Please refer to ** answer, I hope it can help you.

A system of known inequality equations, x+y 450

y＝230x＝220。

<> such as a frank touch of socks let the excitement be noisy.

The interpretation of the gods is shown in the diagram of the blind spine grip seepage in the following paragraph.

f(0)≠0, not zero.

f (x)=0 gives x=-1 which is not a stationary and extreme point. Pick D

1) Derivative of the composite function, f (x) = 2x*e (ax) + x 2*a*e (ax) = (a*x 2+2x) e (ax).

Just discuss g(x)=a*x 2+2x, e(ax) is everbright at zero, don't think about it.

Because a<=0, when a=0, g(x)=2x, it can be seen that when x>=0, f(x)>=0, f(x) monotonically increases Mino Xi; When x<0, f(x) <0 and f(x) decreases monotonically.

When a<0, if the ridge leaks g(x)>=0, x<=0 or x>=-2 a, then f(x)>=0, f(x) increases monotonically; When g(x) < 0, 00 is obtained, and then x>=-2 a should intersect with [0,1], that is, -2 a<=1, that is, -2=if g(x)<0, f(x) decreases monotonically, and the maximum value is f(0)=0

y=sinx is an increasing function on (-pie, pie), so the interval is (- 3 2, 3 2).

What about your question? No, ahh

If you put y=sinx up, as long as there are no two or more x's on 1 y, there will be an inverse function, where xy refers to the original function.

Concept: In general, if the range of the function y=f(x)(x a) is c, if we find a function g(y) where g(y) is equal to x, then the function x= g(y)(y c) is called the inverse of the function y=f(x)(x a), denoted as y=f (-1)(x). The domain and domain of the inverse function y=f (1)(x) are the domain and domain of the function y=f(x), respectively.

The most representative inverse functions are logarithmic and exponential.

Your x has a range, right, but it's okay if you don't have a range!