Given the square X-1 of the function f (x) = sin (2x + 60 °) + sin (2x-60 °) + 2cos, X belongs to R. find the minimum positive period of the function FX, and find the maximum and minimum value of the function FX in the interval [- 45 ° 45 °]

Given the square X-1 of the function f (x) = sin (2x + 60 °) + sin (2x-60 °) + 2cos, X belongs to R. find the minimum positive period of the function FX, and find the maximum and minimum value of the function FX in the interval [- 45 ° 45 °]

F (x) = sin (2x + 60 °) + sin (2x-60 °) + 2cos squared X-1, f (x) = 2Sin (2x) cos60 + cos2x = sin2x + cos2x = Radix 2 (sin2x + 45), so the minimum positive period is Wu. - 45

Let f (x) = cos (x + 2 π of 3) + π of 2cos square, X belongs to R, and find the value range of F (x)

f(x)=cos(x+2π/3)+2cos²π/2=cos(x+2π/3)+2*0=cos(x+2π/3)
∵-1≤cos(x+2π/3)≤1
The value range of the function is 〔 - 1,1]

The function f (x) = SiNx cos (x + π) 6) The value range of is () A. [-2,2] B. [- 3, 3] C. [-1,1] D. [- Three 2, Three 2]

The function f (x) = SiNx cos (x + π)
6)=sinx-
Three
2cosx+1
2sinx
= -
Three
2cosx+3
2sinx
=
3sin(x-π
6)∈[−
3,
3].
Therefore, B

Given the function y = - SiNx cos square x, find the value range

sin^2 x+cos^2 x=1
So y = - SiNx cos ^ 2x = - sinx-1 + sin ^ 2 x = sin ^ 2 x-sinx-1
Let a = SiNx
Then - 1 ≤ a ≤ 1
y=a^2-a-1=(a-1/2)^2-5/4
So a = 1 / 2, y min = - 5 / 4
So a = - 1, y max = 1
So the range is [- 5 / 4,1]

The function f (x) = SiNx cos (x + π) 6) The value range of is () A. [-2,2] B. [- 3, 3] C. [-1,1] D. [- Three 2, Three 2]

The function f (x) = SiNx cos (x + π)
6)=sinx-
Three
2cosx+1
2sinx
= -
Three
2cosx+3
2sinx
=
3sin(x-π
6)∈[−
3,
3].
Therefore, B

Given the function f (x) = 2cos (x + π / 4) cos (x - π / 4) + √ 3sin2x (1), find the minimum positive period (2) of function f (x) if 0

The function can be reduced to f (x) = 2Sin (2x + π / 6), period π and range (- 1,2)

The value range of the function f (x) = 2cos (x + π / 4) cos (x - π / 4) + 3sinx is obtained

F (x) = 2cos (x + π / 4) cos (x - π / 4) + 3sinx = cos (2x) + cos π / 2 + √ 3sinx = 1-2sin? X + √ 3sinx = - 2 (sin? X - √ 3 / 2sinx) + 1 = - 2 (SiNx - √ 3 / 4)? + 11 / 8

The value range of the function y = | cos X - 2cos x is

When cosx ≥ 0, y = cosx-2cosx = - cosx, y ∈ [- 1,0]
cosx

It is known that the odd function f (x) is defined on (- ∞, 0) ∪ (0, + ∞), and is an increasing function on (0, + ∞), f (1) = 0; the function g (θ) = sin2 θ + m · cos It is known that the odd function f (x) is defined on (- ∞, 0) ∪ (0, + ∞), and is an increasing function on (0, + ∞), f (1) = 0; the function g (θ) = sin2, θ + m · cos θ - 2m, θ∈ [0, π / 2]. If the set M = {m| g (θ)

Is the set n = {m| f [g (θ) < 0]} wrong, should be n = {m| f [g (θ)] < 0}?

The minimum positive period of the function f (x) = sin2 π x + cos ^ 2 π x is

f(x)=sin2πx+cos^2πx
=sin2πx+[cos2πx+1]/2
=sin2πx+1/2cos2πx+1/2
Because the minimum positive period of sin2 π X and Cos2 π x is π
Therefore, the minimum positive period of F (x) is π