A little boy asked his father for money to buy books

A little boy asked his father for money to buy books

There is a boy asking his father for money to buy a book.

Dad, what do you say in English

dad,father

（x²-2x）²+2x²-4x+1
The power of the coefficient is 2

(x²-2x)²+2(x²-2x)+1
=(x²-2x+1)²
=(x-1)^4

If the quadratic function f (x) = ax & # 178; + BX + C (C ≠ 0) satisfies f (x + 1) - f (x) = 2x, and f (0) = 1. (1) if the inequality f (x) > 2x + m holds in the interval x ∈ [- 1,1], the value range of real number m is obtained

f(x+1)=f(x)+2x
f(0)=1
1=c
f(1)=f(0)
a+b+1=1==>b=-a
f(x)=ax^2-ax+1
In F (x + 1) = f (x) + 2x, let x = - 1
f(0)=f(-1)-2
f(-1)=3
2a+1=3
a=1
f(x)=x^2-x+1
m

The coordinates of the intersection of the parabola y = 2x & # 178; one 3x x 1 and the X axis are?

Let y = 0 and solve the equation x = 1; - 1 / 2

The vertex of the parabola (1,16), and the distance between the two intersections of the parabola and the x-axis is 8

Let y = a (x-1) \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\a-64 = 60aa = -

A and B start from the same place. If they go in the same direction, B first walks 12 kilometers, then a starts by bike, and it takes another hour to catch up with B. if they go in the opposite direction, after several hours, the distance between a and B is four times that of B. how many kilometers / hour are the two speed?

If you go in the opposite direction, after a few hours, the distance between Party A and Party B is 4 times of the distance that Party B has traveled, which means that the sum of the two speed is 4 times of Party B, and the speed of Party A is 4-1 = 3 times of that of Party B. if the speed of Party B is x, then the speed of Party A is 3x
(3x-x)*1=12
x=6,
3x=18
The speed of a is 18 km / h, and that of B is 6 km / h

Given the point Q (2,0) and the circle C: x ^ 2 + y ^ 2 = 1, the ratio of the tangent length from the moving point m to the circle C to {MQ} is equal to the constant a (a is greater than 0),

Let the coordinate of M be (x, y) & nbsp;, then MQ = under the root ((X-2) ^ 2 + y ^ 2),
The distance from m to the center of the circle is under the root (x ^ 2 + y ^ 2),
The radius of the circle is 1. According to the Pythagorean theorem, the tangent length from m to C is
Under the root (x ^ 2 + y ^ 2-1)

If one root of the equation x2 + X + a = 0 is greater than 1 and the other root is less than 1, the value range of real number a is obtained

Let f (x) = x2 + X + A, then from the known conditions: F (1) = 2 + a ﹤ 0, ﹤ a ﹤ 2

Land area ranking of countries in the world

Russia 1707.5 2 Canada 997.1 3 China 960.1 4 USA 936.4 5 Brazil 854.7 6 Australia 774.1 7 India 328.8 8 Argentina 278.0 9 Kazakhstan 271.7 10 Sudan 250.6 11 Algeria 238.2 12 Congo 234.5 13 Saudi Arabia