A group of letters and words with the same pronunciation, represented by pairs and different by mistakes ( )1.B-bee ( )2.C-say ( )3.D-deer ( )4.G-jeep ( )5.I-eye ( )6.K-key ( )7.M-I'm ( )8.O-oh ( )9.T-tea ( )10.U-you Urgent urgent urgent urgent urgent urgent urgent urgent urgent urgent urgent urgent urgent urgent urgent urgent urgent urgent urgent urgent urgent urgent urgent urgent urgent urgent urgent urgent urgent urgent urgent In a hurry in a hurry in a hurry

( )1.B-bee ( )2.C-say ( )3.D-deer ( )4.G-jeep ( )5.I-eye ( )6.K-key ( )7.M-I'm
( )8.O-oh ( )9.T-tea ( )10.U-you

Find the derivatives of (1) y = x4-5x2; (2) y = xtanx; (3) y = (x + 1) (x + 2) (x + 3) (4) y = lgx-2x

（1）∵y=x4-5x2，∴y′=4x3+10x-3；（2）∵y=xtanx=xsinxcosx，∴y′=(xsinx)′cosx−(cosx)′xsinxcos2x=sinxcosx+xcos2x；（3）∵y=（x+1）（x+2）（x+3），∴y=（x2+3x+2）（x+3），∴y′=3x2+12x+11．（4）∵y=lgx-2x，∴y′=1xln10−2xln2．

What is the value of the formula power of minus two plus the eleventh power of minus two

The power of negative two plus the eleventh power of negative two
=4-2^11

Taxis in a city charge 10 yuan for less than 3 kilometers, and 1.60 yuan for each kilometer for more than 3 kilometers. Uncle Li takes 14 kilometers, how much does it cost?
Don't give the answer directly. I want to know the algorithm

(14-3) * 1.6 + 10 = 27.6 (yuan), 14 kilometers over 3 kilometers, over 11 kilometers, 1.6 yuan per kilometer, a total of 17.6 yuan, the front 3 kilometers to pay 10 yuan, add up to a total of 27.6 yuan

As shown in the figure, Xiao Hong cuts a 4 cm wide strip from a square, and then cuts a 5 cm wide strip from the remaining rectangular paper along the direction parallel to the short side. If the area of the strips cut twice is exactly the same, what is the area of each strip? What is the area of the original square?

Suppose the side length of the square is xcm, then according to the meaning of the question: 4x = 5 (x-4), the solution is: x = 20. Then 4x = 80 (cm2), 20 × 20 = 400 (cm2). Answer: the area of each strip is 80cm2, the area of the original square is 400cm2

Compare the size of a ^ a × B ^ B × C ^ C with (ABC) ^ ((a + B + C) / 3)

a. The logarithms on both sides are: alna + blnb + clnc and ((a + B + C) / 3) (LNA + LNB + LNC) or (alna + blnb + clnc) / (a + B + C) and (LNA + LNB + LNC) / 3. Both sides are average, and the left side is weighted average. The large part is larger, and the small part is larger

Deduction of points for practical problems of mathematical quadratic function
The unit of the dependent variable in the question is ten thousand yuan, and it is listed as the unit element when it is listed. There are three questions, all of which are wrong in the functional relation. The last question is correct, and the solution is wrong. A total of 12 points,

I'm glad to answer for you
You basically don't get much points. When you list it, the unit is not right, but it is wrong. The teacher can give you a little emotional points at most, which is estimated to be 2-5 points. I changed the paper, I know
I wish you a happy study. Be more careful next time

Cut a piece of paper with a side length of 10 cm into the largest circle. What percentage of the area of the circle is that of the square?

The area of the circle: S = π R2 = 3.14 × (10 △ 2) 2 = 78.5 (square centimeter); the area of the square: S = A2 = 10 × 10 = 100 (square centimeter); 78.5 △ 100 = 78.5%; answer: the area of the circle is 78.5% of the area of the square

M is the largest negative number, AB is opposite to each other, CD is reciprocal to each other, what is the square of M + CD + (AB)

M is the largest negative integer
m=-1
AB is opposite to each other
a+b=0
CD is reciprocal to each other
cd=1
m+cd+ (a+b）²=-1+1+0²=0

An applied problem of quadratic equation of two variables
The sum of the purchase price of a and B is 100 yuan, and they are sold at a discount for promotion. If a is 20% off and B is 60% off, they can still earn 50 yuan. If a is 60% off and B is 80% off, they can earn 19.5 yuan. How much is the original purchase price of a and B?

Let a sell price x, B sell price y {x * 0.8 + y * 0.6-100 = 50, X * 0.6 + y * 0.8-100 = 19.5} {x * 2.4 + y * 1.8 = 450, X * 2.4 + y * 3.2 = 478} y * 1.4 = 28, y = 20, so we can get x = 172.5