How to solve the equation 12x + 9x = 60.9 And 3 × 1.8 △ x = 0.6

How to solve the equation 12x + 9x = 60.9 And 3 × 1.8 △ x = 0.6

12x+9x=60.9
Combined, 21x = 60.9
x=60.9/21=20.3/7=2.9
x=2.9
3×1.8÷x=0.6
5.4=0.6x
x=5.4/0.6=9
x=9

How to solve the equation 12x + 9x-1.1 = 0

21x-1.1=0 21x-1.1+1.1=0+1.1 x=0.0523809524

As shown in the figure, the image of the linear function y = x / K + 1 of X and the image of the inverse scale function y = 6 / X both pass through the point (2, m)
Find the relationship between the two functions and the coordinates of the other intersection of the two functions

Take (2, m) into y = 6 / X
So m = 3
So through the point (2,3)
Y = x / K + 1
So 3 = 2 / K + 1
k=1
So the analytic expression of a function is y = x + 1
x+1=6/x
x²+x-6=0
(x-2)(x+3)=0
X = 2 or x = - 3
When x = - 3, y = - 2
So the other intersection is (- 3, - 2)

A quadratic function, when x equals 1, y equals 9; when x equals 3, y equals 9. Its minimum value is 7

According to the meaning of the question, we can know that the symmetry axis of the quadratic function is x = 2. Let the analytic formula of the quadratic function be y = a (X-2) + 7. Substituting x = 1 and y = 9 into the analytic formula, we can get a = 2, so the analytic formula of the quadratic function is y = 2 (X-2) + 7

The waist length of an isosceles right triangle is 3. The area of this triangle is () why is it 6.125

Both right angles are 3.5 with one side as bottom and the other side as high
S = 1 / 2 * 3.5 * 3.5 = 6.125 square decimeter

The straight line y = x + 5-6m intersects the hyperbola y = M-X at the point a of the first quadrant, intersects the x-axis at the point C, AB is perpendicular to the x-axis at the point B, if the s triangle AOB = 3,
Then s triangle AOC =?

Let a (x1, Y1), then s triangle AOB = 1 / 2 * X1 * Y1 = 3, so X1 * Y1 = 6, and a is on hyperbola, so X1 * Y1 = M = 6. The linear and curvilinear equations form a system of equations, and the coordinates of point a (1,6) are solved,
S triangle AOC = s triangle abc-s triangle AOB = 1 / 2 * 6 * 6-3 = 15

Finding the derivative of e ^ SiNx ln (x ^ 2 + 1)

Derivation of compound function [e ^ SiNx ln (x ^ 2 + 1)] '= (e ^ SiNx)' ln (x ^ 2 + 1) * + e ^ SiNx ln (x ^ 2 + 1) '= (e ^ SiNx)' ln (x ^ 2 + 1) * (SiNx) '+ e ^ SiNx * 1 / (x ^ 2 + 1) * (x ^ 2 + 1)' = (e ^ SiNx) 'ln (x ^ 2 + 1) * cos + e ^ SiNx * 2x / (x ^ 2 + 1)

Write the reduplication as it is
Example: breeze (slowly)
Snow () moon () willow ()
Grass () smoke () running water ()

Ai Ai Lang Yi
Luxuriant and graceful

Judge the position relationship between the image of quadratic function y = ax ^ 2 + BX + C and X axis
According to y = ax ^ 2 + BX + C = a (x + B / 2a) ^ 2 + (4ac-b ^ 2) / 4A (a = 0), judge

The premise is that x belongs to all real numbers? If so, discuss (4ac-b ^ 2) / 4A (a is not equal to 0), if the whole > 0, there is an intersection with X axis = 0, there is an intersection with X axis

Given the square of the function y = x - 2x, - 2 ≤ x ≤ a, where a ≥ - 2, find the maximum and minimum value of the function, and find out when the function takes the maximum and minimum value
The value of the corresponding independent variable x

This function is parabola y = (x-1) ^ 2-1, (- 2 ≤ x ≤ a), vertex (1, - 1)
When y '= 2x-2, i.e. x = 1, take the extremum point, i.e. take the minimum point at the vertex
When x = 1, the minimum value of the function is y = - 1
The intersection of function image and X axis at (0,0), (2,0)
When x = - 2, y = 8,
When - 2 ≤ a ≤ 4, the maximum value is y = 8, where x = - 2 or 4
When a > 4, the maximum value is y = a ^ 2-2a, where x = a