Given the function f (x) = 2cos square x + 2sinxcosx + 1, find the minimum positive period of function f (x)

Given the function f (x) = 2cos square x + 2sinxcosx + 1, find the minimum positive period of function f (x)

F (x) = 2cosx-1 + 2sincosx = sin2x + cos2x = √ 2Sin (2x + π / 4) remember the double angle formula sin2x = 2sincosx cos2x = 2cosx-1, so t = 2 π / 2 = π

20. Given the function f (x) = 2sinxcosx + 2cos square x-3, find the minimum positive period of function f (x), monotone increasing interval of function f (x), monotone increasing interval of function f (x)
20. Given the function f (x) = 2sinxcosx + 2cos square x-3, find the minimum positive period of function f (x), the monotone increasing interval of function f (x), the maximum value of function f (x), and find the set that makes it obtain the maximum value

f(x)=2sinxcosx+2(cosx)^2-3
=sin(2x)+cos(2x)
=√2sin(2x+π/4)
=When √ 2Sin [2 (x + π / 8)] minimum positive period T = 2 π / 2 = π 2K π - π / 2 ≤ 2x + π / 4 ≤ 2K π + π / 2 (K ∈ z), the monotone increasing interval of the function is [K π - 3 π / 8, K π + π / 8] (K ∈ z)

Question 2 of exercise on page 11.214: ab = CD, AE perpendicular to BC, DF perpendicular to BF, CE = BF, verify AE = DF
I can't go down. Excuse me!

Fill in the appropriate operation symbols in 1,2,3,4,5,6,7,8,9, and the brackets can form an expression of the number 1999, please write it!

(2+8)*(3+7)*(1+9)*√4-6+5=1999

What is the relationship between the rank of determinant and the value of determinant equal to zero?
When the rank of n-order matrix is n, the value of the corresponding determinant is greater than zero. When the rank of n-order matrix is less than N, the value of the corresponding determinant is equal to zero. Why?

This is the definition of a theorem or the rank of a matrix
The rank of matrix A is equal to the order of the highest nonzero subexpression in a
When the rank of n-order matrix is n, the order of the highest order non-zero sub formula is n, and its n-order sub formula is | a |, so | a | ≠ 0
When the rank of matrix of order n

Fill in the box below with nine numbers 1 to 9 to make the equation true. Each number can only be used once?
□÷□＝□÷□＝□□□÷□□

9 3 6 2 174 78
As soon as I saw this question, I immediately thought of 9 3 6 2. Then the rest came out after a little calculation

Let a be an M × n matrix, C be an invertible matrix of order n, the rank of a is R1, and the rank of B = AC is r, then () A.R > R1 b.R = R1 C.R

Note that the number of rows and columns of AC is the same as that of a, so the right multiplication of a by C is actually the elementary column transformation of a, so
r=r1

There is a regular sequence of numbers 1, 3, 4, 7, 11, 18, 29. The number 2012 of this sequence is odd

a1=1,a2=3,an=a(n-1)+a(n-2)
The first two items are odd, the third item is even, the fourth and fifth items are odd, and the sixth item is even
2012/3=670…… two
Therefore, the number 2012 is odd

How many centimeters is five feet two inches?

1 foot = 30.48 cm. 1 inch = 2.54 cm. Just converted with mobile phone

What is 7 / 8-1 / 3-1 / 6-1 / 12-1 / 24-1 / 48-1 / 96?

Original form
=96 (84-32-16-8-4-2-1)
=21 / 96
=7 out of 32