Answer:
Step-by-step explanation:
Given : 
We have to write which identity we will use to prove the given statement.
Consider
Take left hand side of given expression 
We know
Comparing , we get, a= 180° and b = q
Substitute , we get,
Also, we know 
and 
Substitute, we get,
Simplify , we get,
Hence, use difference identity to prove the given result.
Answer:
C complex
Step-by-step explanation:
a+ bi
a is the real part and bi is the imaginary part
Together they make a complex number
There are 104 boys and 91 girls. 104+91=195 104:91 = 8:7
We want to choose 4 people and we have 6 people to choose from. This is a combination of 6, 4 by 4. Also called <em>six choose four</em>.
The following formula:
Is the combination of 
objects choosen from a total of 
. It's choose .
For our problem, we just need to compute the following:
Thus
Therefore the answer is 15 different combinations
