Answer:
Step-by-step explanation:
cos (x/2)=cos x+1
cos (x/2)=2cos ²(x/2)
2 cos²(x/2)-cos (x/2)=0
cos (x/2)[2 cos (x/2)-1]=0
cos (x/2)=0=cos π/2,cos (3π/2)=cos (2nπ+π/2),cos(2nπ+3π/2)
x/2=2nπ+π/2,2nπ+3π/2
x=4nπ+π,4nπ+3π
n=0,1,2,...
x=π,3π
or x=180°,540°,...
180°∈[0,360]
so x=180°
or
2cos(x/2)-1=0
cos (x/2)=1/2=cos60,cos (360-60)=cos 60,cos 300=cos (360n+60),cos (360n+300)
x/2=360n+60,360n+300
x=720n+120,720n+300
n=0,1,2,...
x=120,300,840,1020,...
only 120° and 300° ∈[0,360°]
Hence x=120°,180°,300°
 
        
             
        
        
        
Answer:
(4,8)
Step-by-step explanation:
4 + 8 = 12
3(4) + 8(8)
= 12 + 64
= 76
 
        
             
        
        
        
Macroeconomics focuses on C) government level. 
Macroeconomics is a branch of economics dealing with the performance, structure, behavior, and decision-making of an economy as a whole rather than individual markets. 
        
             
        
        
        
Answer:
The center is -1,5   and the radius is 2 
Step-by-step explanation:
Subtract 22 from both sides of the equation. x 2 + y 2 + 2 x − 10 y = − 22 Complete the square for x 2 + 2 x . ( x + 1 ) 2 − 1 Substitute ( x + 1 ) 2 − 1 for x 2 + 2 x in the equation x 2 + y 2 + 2 x − 10 y = − 22 . ( x + 1 ) 2 − 1 + y 2 − 10 y = − 22 Move − 1 to the right side of the equation by adding 1 to both sides. ( x + 1 ) 2 + y 2 − 10 y = − 22 + 1 Complete the square for y 2 − 10 y . ( y − 5 ) 2 − 25 Substitute ( y − 5 ) 2 − 25 for y 2 − 10 y in the equation x 2 + y 2 + 2 x − 10 y = − 22 . ( x + 1 ) 2 + ( y − 5 ) 2 − 25 = − 22 + 1 Move − 25 to the right side of the equation by adding 25 to both sides. ( x + 1 ) 2 + ( y − 5 ) 2 = − 22 + 1 + 25 Simplify − 22 + 1 + 25 . ( x + 1 ) 2 + ( y − 5 ) 2 = 4 This is the form of a circle. Use this form to determine the center and radius of the circle. ( x − h ) 2 + ( y − k ) 2 = r 2 Match the values in this circle to those of the standard form. The variable r represents the radius of the circle, h represents the x-offset from the origin, and k represents the y-offset from origin. r = 2 h = − 1 k = 5 The center of the circle is found at ( h , k ) . Center: ( − 1 , 5 ) These values represent the important values for graphing and analyzing a circle. 
 
        
             
        
        
        
Answer:B.
Step-by-step explanation: I took the same class