Answer:
In statistics and econometrics, the first-difference (FD) estimator is an estimator used to address the problem of omitted variables with panel data. It is consistent under the assumptions of the fixed effects model. In certain situations it can be more efficient than the standard fixed effects (or "within") estimator.
First differences are the differences between consecutive y-‐values in tables of values with evenly spaced x-‐values. If the first differences of a relation are constant, the relation is _______________________________ If the first differences of a relation are not constant, the relation is ___________________________
Answer:
Step-by-step explanation:
Okay!
A graph representing the function :
f(x)=x(x+2)
I will describe the graph for you!
the points on this graph are : (-3,3),(-2,0),(-1,-1),(0,0),(1,3)
the graph also creates a U shape!
Answer:
θ = -33.69°
Step-by-step explanation:
For Φ>0 and Φ<0 (in general Φ≠nπ where n is an integer), sin(Φ) ≠ 0
Dividing both equations:

Therefore:
arctan(θ) = -2/3
θ = -33.69°
The answer does not depend on the sign of Φ, in fact we just need that the sine does not become zero, which occurs when Φ is equal to an integer times π (radians) or 180 (degrees)
Have a nice day!
We are tasked to solve the three angles given that we have the measurements of the sides such as
a = Zack to Rachel distance
b = Rachel to Maddie distance
c = Maddie to Zack distance
a =3
b =2.5
c =4
Solving the angles we need to use Law of Cosines:
cos A = 2.5² + 4² -3² /2*2.5*4
A = 48.59°
cos B=3² + 4² - 2.5² / 2*3*4
B = 38.625°
C=180 - 48.59° - 38.625°
C= 92.79°
The three angles are 48.59°,38.63° and 92.79°.