Find 28 math problems in high school math and solve several math problems in senior sophomores

Do you want a problem, there are a lot of them, there are all the Olympiads, what are you mainly doing, if you want it, tell me the mailbox.

The slope of a straight line that passes a and is perpendicular to the line l is 1 The coordinates of 3a are (-4,4) So the equation for a straight line perpendicular to the line l is x-3y+16=0

The distance from a to 3x+y-2=0 is the root number 10

So the square of the radius is (root number 10) + 2 times the root number 6 2) =16, so the equation for the garden is (x+4) +x-4) =162 function f(x)=ax +(b-2)x+3(a≠0), if the inequality f(x)>0 solution set is (-1,3).This can be seen from the image.

a＜0 x1 . x2=3/a=-3

So a=-1 x1+x2=(2-b) a =2 so b=4, so f(x)=-x +2x+3

The minimum value on x [m,1] is 1

The axis of symmetry of f(x) is x=1 and the minimum value is obtained at m on the left side of the axis of symmetry, so f(m)=1 so m=1- root number 33 a +b a b + ab

You should be mistaken about this topic.

I think it should be proof that a +b a b+ab is cube then the left side is equal to (a+b)(a -ab+b ) and the right side = ab(a+b).

Left-Right = (a+b)(a-2ab+b) = (a+b)(a-b) Because a,b,c>0

So a+b)(a-b) 0

So a +b a b + ab

If a+b+c=1, it is only necessary to prove a +b+c (a+b+c) 3(a +b +c) from the above conclusion This is well proved.

(1) The straight line is 3x+y-2=0, so the slope k1=-3, so the straight line l slope k2=1 3 that passes through the point a and is perpendicular to the straight line 3x+y-2=0 is x+3y-16=0

2) The distance from point a to the straight line d=|-4×3+4-2|÷√9+1）=√10.

radius r=4

The equation is (x+4) squared + (y-4) squared = 16

Substituting (-1,0)(3,0) into the equation makes the equation equal to 0, and solving the equation yields a=-1 , b=4

1) Proof of: a +b -a b-ab = a(a-b) + b(b-a) = a(a-b)-b(a-b) = (a-b) 0

So a +b a b + ab

1) The focus is on the x-axis, i.e., 2*a=10, a-b =16, and a, b, respectively, to obtain x 5 + y 3 = 1

2) Let the coordinates of m and n, AB equation y=k1(x-4), cd equation y=k2(x-4).

For a system of simultaneous equations, the coordinates of m and n are expressed as x1+x2, y1+y2.

Write out the general expression of the mn equation and then judge.

1)y=45*x+6480/x-360

2) x>0, which is 540 from the basic inequality

y =ax(a>0) let f(a 4,0).

Straight line l: y=2*x-a2

Point a(0,-a 2).

The distance from the origin to the straight line l d= 5*a 10

Area s=1 2*d*|af|

The solution is a=8, that is, there is y =8x

Oh my God. When I saw it, my head was covered...

y=x(1-x)=x-x 2=-x 2+x recipe: y=-x 2+x=-(x 2-x)=-(x 2-x+1 4)+1 4=-(x-1 2) 2+1 4

From the properties of the quadratic function, the function opens downward, and has a maximum value when x = 1 2, y is maximum, and the maximum value at this time is y = 0 + 1 4 = 1 4

The apex is at the origin of the noise, and the joke digs the code, draws the picture, and you can find it.

1）sin2x=-3/5;cos2x=4/5sin2x=2sinx*cosx=-3/5;(sinx)^2+(cosx)^2=1

sinx=1 root number 10; cosx=-3 root number 10;

2)tan3x=(-1/3-3/4)/(1-1/4)=-13/9

The answer is obviously complicated, and your method is completely correct.

In fact, here is the omission of the questioner, the questioner originally wanted to be linked, but he didn't expect to directly substitute the linear equation.

Answer: Question 1, 250

Question 2, Question 3,.

Solution 1: Use the properties of the equation, for example, in the first problem, the right side is reduced by 10 times from 10 (-9) to 10 (-10), then the 25 on the left must be magnified by 10 times, that is, 250, in order to ensure that the value of the equation remains unchanged.

Solution 2: Equation method, let the value in the question mark be a, then a=25 10 (-9) 10 (-10)=250.

Solution 3: Decomposition method, 25 10 (-9) = 25 10 10 (-10) =

This question tests the application of scientific notation, and the two sides of the equation are equal, so if you multiply 10 in the front, you should divide by 10 in the back, so as to ensure that the two sides of the equation are equal.

The rules for the operation of power functions with the same base.

10^a*10^b=10^(a+b)