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:
RT = 20
Step-by-step explanation:
Point S is on line segment
R------------S------------T
RS + ST = RT
Given
ST=3x-8
RT=4x
RS=4x-7,
Step 1
We find x
4x - 7 + 3x - 8 = 4x
4x + 3x -7 - 8 = 4x
7x - 15 = 4x
7x - 4x = 15
3x = 15
x = 15/3
x = 5
Step 2
We find RT
RT = 4x
x = 5
RT = 4 × 5
RT = 20
The numerical length of RT is 20
Answer: in statistics deviation is the difference between the value of one number in a series of numbers and the average value of all numbers in the series ( i hope this helped)
Step-by-step explanation:
Answer: 0.27
Step-by-step explanation:
Move the decimal two places to the left