Answer:
B and C
Step-by-step explanation:
I hope this helps :)
The picture wont load for me :/
For this case we first write the equation of which we will use:
I (db) = 10log (l / l)
We substitute the value of l.
We have then:
l = 10 ^ 8lo
Substituting in the given equation:
I (db) = 10log ((10 ^ 8lo) / lo)
Rewriting:
I (db) = 10 * log (10 ^ 8)
I (db) = 80
Answer:
I (db) = 80
option 4
Answer: 720 because 3*3=9 and 240*3=720
Step-by-step explanation:
Answer:
See below.
Step-by-step explanation:
First, use the co-function identity:
We can turn the second term into cosine:
Substitute:
Now, use the sum to product formulas. We will use the following:
Substitute:
Use the even-odd identity:
Therefore:
Replace the second term with the original term:
Proof complete.