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:
2nd - (w - 5)(w + 5)
4th - (-4v - 9)(-4v + 9)
Step-by-step explanation:
1. The first option shows an expression multiplied by its opposite(x -1), so therefore, it does not show the difference of squares
2. The second option does show the difference of squares because it is in the form (a + b)(a - b)
3. The third option is just a square because the same expression is multiplied by itself.
4. The fourth option is the difference of squares because it is in the form (a + b)(a - b). a equals -4v and b equals 9 in this case.
5. The fifth option is not the difference of squares. No term in common in both expressions
6. The sixth option is just a square because the same expression is multiplied by itself.
In all, there are two options that are the difference of squares, the 2nd and 4th.
Answer:
i dont understand
Step-by-step explanation:
Answer:
256
Step-by-step explanation: