Find the area enclosed by parabola y = x & # - x, straight line x = - 1 and X axis?

Find the area enclosed by parabola y = x & # - x, straight line x = - 1 and X axis?

The enclosed area = 0.84 & nbsp; as shown in the figure:

E ^ X / (1 + e ^ 2x) DX for indefinite integral

Girls are 2 / 5 more than boys and boys are less than girls
&There are two bags of rice. The second bag weighs 4 / 5 of the first bag. If you take 8 kg from the first bag and put it into the second bag, and the two bags are the same weight, how many kg are the two bags of rice?
&3. & nbsp; & nbsp; 15 meters is 1 / 6 less than ()
&4. & nbsp; & nbsp; & nbsp; () 1 / 5 more than 15m
&The current price of the tape recorder is 368 yuan, 2 / 25 lower than the original price. How much is the price reduction?
&6. & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; after selling two fifths of the original color TV sets, the seller bought 120 sets. Now the number is 4 / 15 less than the original. How many original color TV sets?
Formula

1 + 2 / 5 = 7 / 5, 2 / 5 divided by 7 / 5 = 2 / 78 * 2 = 16, 16 / (1-4 / 5) = 16 divided by 1 / 5 = 8015 / (1-1 / 6) = 15 divided by 5 / 6 = 18m15 * (1 + 1 / 5) = 15 * 6 / 5 = 18m368 / (1-2 / 25) = 368 divided by 23 / 25 = 400 yuan, 400-368 = 32 yuan, 1-4 / 15 = 11 / 15, 1-2 / 5 = 3 / 5, 11 / 15-3 / 5 = 2 / 15, 120 divided by 2 / 15 = 900 units

Parallelogram rule (with additional points)
I'm a freshman in senior high school. Now I'm preparing my physics course for senior high school one at home. Suddenly, I read a passage from my tutor's book: "when adding scalars, you just need to add them according to the arithmetic. Otherwise, you can't add and subtract vectors directly. You should follow the parallelogram rule." what's the parallelogram rule here and how to use it?

Parallelogram rule
Open classification: Physics, rules
When two forces are combined, take the directed line segment representing the two forces as the adjacent edge to make a parallelogram. The diagonal line between the two adjacent edges represents the magnitude and direction of the resultant force. This is called the parallelogram rule
If you think this entry needs to be improved and new content needs to be added or wrong content needs to be modified, please edit the entry

One basket of eggs, two, two, one, three, three, two, four, four, three, five, five, four, six, six, five, how many eggs are there in this basket?

3*4*5-1=59

By knowing three points a (0,2, - 1), B (- 1,4,1), C (- 2,1,1), it is proved that a triangle with ABC as its vertex is an isosceles triangle,

ab=√(0+1)^2+(2-4)^2+(-1-1)^2=3
ac=√(0+2)^2+(2-1)^2+(-1-1)^2=3
So it's an isosceles triangle

The problem of derivative function of calculus f (x) = one third power of X, (1) prove that f '(0) does not exist. (2) prove that in y=
The problem of derivative function of calculus
F (x) = one third power of X,
(1) It is proved that f '(0) does not exist
(2) It is proved that there is a vertical tangent at the third power of y = X
Prove by limit

f(x)=x^(1/3)
f'(x)=(1/3)x^(-2/3)
When x = 0, x ^ (2 / 3) = 0, take the reciprocal) x ^ (- 2 / 3) is meaningless, so f '(0) does not exist
The tangent of the vertical x-axis, i.e. the derivative is infinite, which is obtained at x = 0 (graphically)
A tangent perpendicular to the y-axis does not exist because f '(x) is not equal to 0

Subtraction is additive______ Operation

Subtraction is the inverse of addition

How to find the derivative of y = SiNx ^ 2-sin3x
y=sinx^2-sin3x
y=x^2／(2x+1)^3
y=e^2x*cosx

Basically, the results come out in one or two steps
y'=2xcosx^2-3cos3x
Y '= [2x (2x + 1) ^ 3-2 * 3 (2x + 1) ^ 2] / (2x + 1) ^ 6
Y '=. This is a little ambiguous. Let's put the title in brackets
Hope to adopt

Have you taught three digit addition and subtraction in the first grade of primary school