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The motorcycle wheels rotate rapidly and look like a whole plane, which shows that______ ．
A wheel is like a round surface, which is formed by rotation of an axis. This axis is regarded as a line
1. Know that the circle passes through two points a (- 1,0), B (3,2), and the center of the circle is on the straight line y = x, and find the equation of the circle
1. Know that the circle passes through two points a (- 1,0), B (3,2), and the center of the circle is on the straight line y = x, and find the equation of the circle
2. The fixed cost of a factory to produce a kind of machine is 5000 yuan. For every 100 machines produced, it needs to increase 25000 yuan. The market demand for machines is 500, and the sales revenue is 10000 yuan, f (T) = the square of 5t-0.5t (0 is less than or equal to t, less than or equal to 5), among which is the number of machines sold (100). 1, What's the most profitable factory?
1. Know that the circle passes through two points a (- 1,0), B (3,2), and the center of the circle is on the straight line y = x, and find the equation of the circle
Let the center of the circle be (a, a)
According to the meaning of the title, the distance from the center of the circle to a and B is equal
√（a+1）²+a²=√（a-3）²+（a-2）²
a²+2a+1+a²=a²-6a+9+a²-4a+4
2a+6a+4a=12
12a=12
a=1
Radius = √ (1 + 1) & sup2; + 1 & sup2; = √ 5
Equation: (x-1) & sup2; + (Y-2) & sup2; = 5
2. The fixed cost of a factory to produce a kind of machine is 5000 yuan. For every 100 machines produced, it needs to increase 25000 yuan. The market demand for machines is 500, and the sales revenue is 10000 yuan, which is the square of F (T) = 5t-0.5t (0 less than or equal to t less than or equal to 5). Among them, it is the problem of the number of machines sold (100 sets). 1, Unit: 100 sets) 2. When the annual output is what, the profit of the factory is the largest?
Set the annual profit as S
S=5T-0.5T²-0.5-500/100×0.25=-1/2T²+5T-1.75
=-1/2(T²-10T)-1.75
=-1/2(T-5)²+10.75
Because 0 ≤ t ≤ 5
S is a quadratic function. When t = 5, the maximum profit is 107500 yuan
Let's send a batch of goods to Party A and Party B according to the score of 5:3. Party A completes 80% of the task of the team, and the rest is sent to Party B. Party B has transported 480 tons in total. How many tons are there in this batch of goods?
5X/8*20%+3X/8=480
X = 960 tons
If the root of the equation 2A + 5 / 3 = 5x + 1 / 3 is negative, then the value range of a is____ .
2a+5 5x+1
____ = _____ Here are the two scores above
3 3
Hateful Mathematics !
Both sides are the same as X3 ~: 2A + 5 = 5x + 1,
5X=2a+4,
X=2a+4/5,
Because of X
A pile of cone-shaped yellow sand is 25.12 meters long and 1.5 meters high. The weight of yellow sand per cubic meter is 1.5 tons. How many tons of sand are planted in this pile
25.12 ﹣ 3.14 ﹣ 2 = 4 (m) 4 × 4 × 3.14 = 50.24 (M2) 50.24 × 1.5 ﹣ 3 (or × one third) × 1.5 = 37.68 (T)
We know the line L1: y = 2x + 4. (1) find the analytic expression of the line L2 with Y-axis symmetry, and observe the analytic expressions of L1 and L2 to see what kind of laws exist
If line L1: y = 2x + 4, then the two points intersecting with X and Y axes are (- 2,0), (0,4) suppose that line L2: y = ax + B is symmetric about y axis and line L1, then the two points intersecting with X and Y axes are (2,0)), (0,4). Substituting these two points into line L2: y = ax + B, we can get a = - 2, B = 4, that is, line L2: y = - 2 + 4
There are 56 students in the class. Boys are 25% less than girls
56 △ 1 + (1-25%), = 56 △ 1.75, = 32 (person); answer: there are 32 female students
Cross multiplication: the square of 6x - the result of 13X + 6,
The square of 6x-13x + 6
=(2x-3)(3x-2)
The number of boys is equivalent to two-thirds of the number of girls. There are 50 students in the class. How many boys are there?
There are 35 boys
Give me a reward
Let the tangent equation of the image of the function y = f (x) = AX3 + bx2 + CX + D at x = 0 be 24x + Y-12 = 0. (I) find C, D; (II) if the extreme value of the function is - 16 at x = 2, try to find the analytic expression of the function and determine the monotone interval of the function
(I) ∵ f '(x) = 3ax2 + 2bx + C, ∵ f' (0) = C; --- (1 point) ∵ the slope of tangent 24x + Y-12 = 0 is k = - 24, ∵ C = - 24; --- (2 points) substituting x = 0 into 24x + Y-12 = 0 to get y = 12, ∵ P (0,12), --- (3 points) ∵ d = 12
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