Solve a cubic equation with one variable, x ^ 3 + 6x ^ 2 + 11x-42 = 0, etc

Solve a cubic equation with one variable, x ^ 3 + 6x ^ 2 + 11x-42 = 0, etc

X1=1.72594240448847;
X2=-3.86297120224423 + 3.06789587521708 i;
X3=-3.86297120224423-3.06789587521708 i
Solve the equation with proper method: 1. (5x-3) (x + 1) = (x + 1) square + 52. (x + 5) square-2 (x + 5) - 8 = 0.3. (x-1) (x + 2) = 70
4. The square of X - (3 + 2 times radical 3) x + 5 + 3 times radical 3 = 0
(5x-3) (x + 1) = (x + 1) ^ 2 + 5, deformation 4x ^ 2-9 = = 0, factorization (2x-3) (2x + 3) = = 0, the solution is x = ± 1.5
(x + 5) ^ 2-2 (x + 5) - 8 = = 0, deformation x ^ 2 + 8x + 7 = = 0, factorization (x + 1) (x + 7) = = 0, the solution is X1 = - 1, X2 = - 7
(x-1) (x + 2) = = 70, deformation x ^ 2 + x-72 = = 0, factorization (X-8) (x + 9) = = 0, the solution is X1 = 8, X2 = - 9
X ^ 2 - (3 + 2 √ 3) x + 5 + 3 √ 3 = = 0, the simple method has not thought of, the solution is X1 = 2 + √ 3, X2 = 1 + √ 3
How to solve the equation of square of X + 5x - 6 = 0
Because it's very difficult to review for self-study examination, I hope you can help me. Thank you very much!
Thank you! But I still can't understand it. Can you tell me more about it? How to get x (X-6) (x-1) = 0
x^2+5x-6=0
(x+6)(x-1)=0
x1=-6
x2=1
x^2+5x-6=0
(x-6)(x+1)=0
x1=6
x2=-1
The sum of two roots is equal to a term, and the multiplication of two roots is equal to a constant term. I forgot the specific solution, sorry.
The square of (5x-1) - 3 (5x-1) = 0 is solved by equation
The square of (5x-1) - 3 (5x-1) = 0
(5x-1)(5x-1-3)=0
(5x-1)(5x-4)=0
5x-1=0 5x-4=0
∴X1=1/5
X2=4/5
(5x-1)²-3(5x-1)=0
(5x-1)(5x-1-3)=0
(5x-1)(5x-4)=0
X = 1 / 5 or x = 4 / 5
Hope to help you
If you have any questions, you can ask.
Thank you for your adoption
Given that the variables X, y satisfy the inequality system [(x greater than or equal to y), (x + y less than or equal to 4), (y greater than or equal to m)] z = x + 2Y, the maximum value is 9 greater than the minimum value, then the value of real number m is____ ?
In the region of x > = y, x + y = M
X=y
x+y=4
The solution is x = 2, y = 2
The maximum value of Z = x + 2Y = 2 + 2 × 2 = 6
x=y y=m x=m
The minimum value of Z = x + 2Y = m + 2m = 3M
Max min = 6-3m = 9
3m=-3
m=-1
Given that the variables X, y satisfy the inequality system [(x greater than or equal to y), (x + y less than or equal to 4), (y greater than or equal to m)] z = x + 2Y, the maximum value is 9 greater than the minimum value, then the value of real number m is__ m=-1
On the simple problem of finding the maximum and minimum of quadratic function
A village plans to build a channel, its cross section is isosceles trapezoid, the bottom angle is 120 degrees, the sum of two waist and bottom is 6m. How to design, make the cross section area maximum? What is the maximum area?
If it's not convenient to draw a picture, I'll try to tell you more about it. Let's set the waist length as X and the bottom as y, because the bottom angle is 120 ° and make two auxiliary lines to know that the length of the top and bottom (that is, the width of the upper mouth of the canal) is (x + y), and the height (that is, the depth of the canal) is √ 3x / 2 (root of two is three)
If the length of the rectangle is 3 under the root sign and the width is 6 under the root sign, then the diagonal length of the rectangle is and the area is
√（6+12)=3√2
2√3×√6=6√2
If the variables X and y satisfy the constraint conditions that X-Y + A is less than or equal to 0, x + y is greater than or equal to 0, y is greater than or equal to 1, (a is less than zero), and the maximum value of Z = x-2y is 3
What is the value of a
Known & nbsp; X-Y + a ≤ 0
         x＋y≥0
         y≥1
The shadow part as shown in the figure meets the requirements,
Z = x-2y, transformed to y = 1 / 2 * (x-z)
When the line y = 1 / 2 * (x-z) is as shown in the figure, - 1 / 2 * Z is the smallest and Z is the largest,
The critical point is the intersection of X-Y + a = 0 and y = 1, (1-A, 1)
There is Z = 1-2-1
The solution is a = - 4
Find the coordinates of the image vertex of the following quadratic function, the maximum and minimum of the function y = 2x & # 178; - 8x + 1, y = - X & # 178; + 2x + 4
y=2x^2-8x+1=2(x^2-4x)+1=2(x-2)^2-8+1=2(x-2)^2-7
The vertex is (2, - 7), and the minimum is - 7
y=-x^2+2x+4=-(x^2-2x)+4=-(x-1)^2+1+4=-(x-1)^2+5
The vertex is (1,5), and the maximum value is 5
It is known that the diagonal length of the rectangle is 4cm, and the length of one side is 3cm, then the area of the rectangle is?
I want high accuracy
A diagonal divides a rectangle into two triangles
The diagonal of a rectangle is the hypotenuse of a right triangle
The square of a plus the square of B equals the square of C
That is to say, the length of the other side is equal to the square of 4 minus the square of 2 root sign 3
It is equal to 2
The area of a rectangle is equal to the length times the width
The area of a rectangle is equal to 2 times 2 root sign 3, which is equal to 4 root sign 3 square cm
(Note: ∵ is a mathematical symbol because ∵ is a mathematical symbol)
The diagonal divides the rectangle into two triangles. The diagonal of the rectangle is the hypotenuse of the right triangle. According to "the sum of the squares of the two right sides is equal to the square of the hypotenuse", the other right side is 2cm
The area of the rectangle is 4 times of the root sign and 3 square cm.
4 roots 3