When x > - 1, find the minimum value of the function y = x * 2-2x-2 / x + 1

When x > - 1, find the minimum value of the function y = x * 2-2x-2 / x + 1

Seeing that the denominator is x + 1 and the domain of definition is x > - 1, we realize that this is the mean value inequality. Generally, the mean value inequality under this condition is the first choice. Generally, in order to use the mean value inequality, we use the rounding method
y=(x^2-2x-2)/x+1=(x^2+2x+1-4x-4+1)/x+1=x+1+1/(x+1)+4>=2+4=6.

Find the maximum and minimum value of the function f (x) = │ 2x ^ 3 - (9x ^ 2) + 12x in the closed interval [- 1 / 4.5 / 2]

Because 2x ^ 2-9x + 12 = 2 (X-9 / 4) ^ 2 + 15 / 8 > 0,
So when x

Find the minimum value of the function y = 9x & # 178; + 1 / 2x & # 178

19/2

In rectangular ABCD, the vertical plane Abe of AD, AE = be = BC = 2, f belongs to CF, and the vertical plane ace of BF is: AE / / BFD. 2) VC BGF

(1) Connect the intersection of AC and BD with point O ∵ BF ⊥ plane ace, and CE ∈ plane ace, ∵ BF ⊥ CE, and ∵ be = BC, ∵ BF ⊥ CE, and CF = EF. In △ ace, ∵ f is the midpoint of CE, O is the midpoint of AC, ∵ fo is the median of △ ace, ∵ of ∥ AE, ∵ of ∈ plane BDF, ∥ AE ∥ plane BDF (this is the first question)

1 2 3 4 5 = 21, fill in the calculation symbol in the space

1×（-2+3）+4×5=21

In linear algebra, if the rank of a matrix of order n is less than N, does the corresponding determinant equal to zero? If it is m times n matrix and the rank is less than N, is it the same?

When m is not equal to N, there is no determinant for mxn matrix

Use 1, 3, 6, 4 and 7 to form the following formula (each number can only be used once) () - () = () - () = ()

（ 7）—（ 6）=（ 4）—（3 ）=（1 ）

It is proved that a matrix A is positive definite if and only if its positive inertia index and rank are equal to n

First of all, we should know the conclusion: the nondegenerate linear transformation does not change the positive definiteness of quadratic form, so we may as well let a = diag (D1, D2 Let f (x1, X2,..., xn) = x ^ tax = d1x1 ^ 2 +. + dnxn ^ 2 , xn) ^ t ≠ o, f (x1, X2,...)

In sequence 1, 1, 2, 3, 5, 8, 13, 21 From the third number, each number is the sum of the first two numbers. How many even numbers are there in the first 100 numbers? How many odd numbers are there in the first 500?

Because their arrangement rule is odd, odd, even, so: (1) 100 ÷ 3 = 33 1，（2）500÷3=166… Among the top 100 numbers, there are 33 even numbers and 334 odd numbers

How many centimeters is five feet six inches

About 1.676 meters