Answer:
The work is in the explanation.
Step-by-step explanation:
The sine addition identity is:
.
The sine difference identity is:
.
The cosine addition identity is:
.
The cosine difference identity is:
.
We need to find a way to put some or all of these together to get:
.
So I do notice on the right hand side the 
and the 
.
Let's start there then.
There is a plus sign in between them so let's add those together:
![=[\sin(a+b)]+[\sin(a-b)]](https://tex.z-dn.net/?f=%3D%5B%5Csin%28a%2Bb%29%5D%2B%5B%5Csin%28a-b%29%5D)
![=[\sin(a)\cos(b)+\cos(a)\sin(b)]+[\sin(a)\cos(b)-\cos(a)\sin(b)]](https://tex.z-dn.net/?f=%3D%5B%5Csin%28a%29%5Ccos%28b%29%2B%5Ccos%28a%29%5Csin%28b%29%5D%2B%5B%5Csin%28a%29%5Ccos%28b%29-%5Ccos%28a%29%5Csin%28b%29%5D)
There are two pairs of like terms. I will gather them together so you can see it more clearly:
![=[\sin(a)\cos(b)+\sin(a)\cos(b)]+[\cos(a)\sin(b)-\cos(a)\sin(b)]](https://tex.z-dn.net/?f=%3D%5B%5Csin%28a%29%5Ccos%28b%29%2B%5Csin%28a%29%5Ccos%28b%29%5D%2B%5B%5Ccos%28a%29%5Csin%28b%29-%5Ccos%28a%29%5Csin%28b%29%5D)
So this implies:
Divide both sides by 2:
By the symmetric property we can write:
Answer:
The two iterations of f(x) = 1.5598
Step-by-step explanation:
If we apply Newton's iterations method, we get a new guess of a zero of a function, f(x), xₙ₊₁, using a previous guess of, xₙ.
xₙ₊₁ = xₙ - f(xₙ) / f'(xₙ)
Given;
f(xₙ) = cos x, then f'(xₙ) = - sin x
cos x / - sin x = -cot x
substitute in "-cot x" into the equation
xₙ₊₁ = xₙ - (- cot x)
xₙ₊₁ = xₙ + cot x
x₁ = 0.7
first iteration
x₂ = 0.7 + cot (0.7)
x₂ = 0.7 + 1.18724
x₂ = 1.88724
second iteration
x₃ = 1.88724 + cot (1.88724)
x₃ = 1.88724 - 0.32744
x₃ = 1.5598
To four decimal places = 1.5598
10x20x2=$400
All you have to do is find the area of the floor(10x20=200),then you just multiple the area by the cost(200x$2=$400),and that is how you find the cost.
