How to calculate that the square of x minus 15x minus 50 equals 0?

x^2-15x-50=0
(x-10)(x-5)=0
X = 10 or 5

Let vector group a 1, a 2, a 3, a 4, a 5 be linearly independent

k1(a1+a2)+k2(a2+a3)+k3(a3+a4)+k4(a4+a5)=0k1a1+(k1+k2)a2+(k2+k3)a3+(k3+k4)a4+k4a5=0=> k1=0 (1) andk1+k2=0 (2) andk2+k3=0 (3) andk3+k4=0 (4) andk4 =0from (1) (2)k2=0from (3)k3=0ie k1=k2=k3=k4=0=> a1+a2,...

(2 + 1) * (2's square + 1) * (2's fourth power + 1); (2's 128th power + 1) + 1

After multiplying (2-1) = 1 by the square difference formula repeatedly, the result remains unchanged (2 + 1) * (2 ^ 2 + 1) * (2 ^ 4 + 1)... * (2 ^ 128 + 1) + 1 = (2-1) (2 + 1) (2 ^ 2 + 1) (2 ^ 4 + 1) *... * (2 ^ 128 + 1) + 1 = (2 ^ 2-1) (2 ^ 2 + 1) (2 ^ 4 + 1) *... * (2 ^ 128 + 1) + 1 =. = (2 ^ 128-1) (2 ^ 128 + 1) + 1 = 2 ^ 256-1 + 1 = 2 ^ 25

Let the first n terms and Sn of the arithmetic sequence be known as A3 = 12 S12 > 0 S13

S12=12a1+12×11d/2
=12(a3-2d)+66d
=12a3+42d
=42d+12×12
=42d+144>0
d>-24/7
S13=13a1+13×12d/2
=13(a3-2d)+78d
=13a3+52d
=52d+13×12
=52d+156

If the left side of the quadratic equation x ∧ 2 + MX + m + 3 = 0 with respect to X is a complete square, the value of M is obtained
X Λ 2 is the square of X
Good answer, plus points
I prefer phenylacridine

The left side of the quadratic equation x ∧ 2 + MX + m + 3 = 0 is a complete square,
It shows that the equation should have two equal roots, so the discriminant
b^2-4ac=m^2-4(m+3)=0
The solution is m = 6 or M = - 2
The left side of the univariate quadratic equation x Λ 2 + MX + m + 3 = 0 of X is a complete square, so the left side can be written as (x-a) ^ 2 = 0
So the equation has two equal roots, so the discriminant is zero

In the plane rectangular coordinate system, the coordinates of vertex A and B of triangle ABC are (- 1, - 2) (3, - 2) respectively, and vertex C moves on the straight line
When the area of triangle ABC is 6, it is the coordinate of point C
2 when the triangle ABC is an isosceles triangle with ab as the base, the coordinates of point C are obtained

1. Which line does vertex C move on? The line told should be able to determine the abscissa of point C, and its ordinate should be 1 or - 5. Find out the length of line AB as 4, use the triangle area formula to find out the height as 3, set the ordinate of point C as x, then the absolute value of X + 2 is equal to 3, and then find out x, that is, the ordinate of point C
2. In isosceles triangle, point C moves on the straight line x = 1 (y is not equal to - 2). If the area is still 6, then C (1,1) or (1, - 5). If the area is not 6, then the ordinate of C can be obtained according to the method of the first question above

It is known that the fourth power of (a + 1) = the fourth power of a + the third power of 4A + the square of 6A + 4A + 1. If s = (x-1) the fourth power + the third power of 4 (x-1) + the square of 6 (x-1) + 4x-3, then s = ()
The fourth power of a (X-2). The fourth power of B (x-1)
The fourth power of Cx. The fourth power of D (x + 1)
Xueba to help, there must be a process!

Let a = X-1
Get it
therefore
S = (x-1 + 1) to the fourth power = x to the fourth power
Choose C

1 / 22111 / 2222,11 / 222,11 / 222,11 / 22 compare size

Put it in Excel and you can sort it
The table says: = 1 / 22,
=111/2222
.
Then sort
11/22>11/222=11/222>111/2222>1/22

2X + y = 1, find the minimum value of 4x + 2Y (where x.y is exponential)
RT

4 ^ x + 2 ^ y ≥ 2 √ (4 ^ x * 2 ^ y) this is the arithmetic mean greater than or equal to the geometric mean
=2√(2^2x+2^y)
=2√2^(2x+y)
=2√2
If and only if 4 ^ x = 2 ^ y, that is, 2x = y = 1 / 2, it is equal sign
So the minimum value of 4 ^ x + 2 ^ y is 2 √ 2

There is an electric fan marked with "220v55w". If the resistance of the motor coil of the fan is 8 Ω, when it works normally, the electric power supplied by the power supply is W. What is the power converted into wind power W. What is the heating power of the motor__ W．

In normal operation, the electric power is the rated power 55W marked on the nameplate. At this time, the current passing through the fan is: I = Pu = 55220a = 0.25A, the heating power of the fan motor is: P0 = I2R = 0.252 × 8W = 0.5W, so the output power of the fan is: P '= p-p0 = 55-0.5 = 54.5w, and the output power is the power converted into wind energy

How to calculate that the square of x minus 15x minus 50 equals 0?