Answer:
The correct answer is option D:
Step-by-step explanation:
Given:
log(y)= 3.994
Solution:
A logarithm base b of a positive number x satisfies the following definition:
For
Also if no base b is indicated, the base of the logarithm is assumed to be 10 .
Thus, in log(y)= 3.994 base b is not indicated. so its base is assumed to be 10
now
Then
Answer:
sin(-a)= -15 /17
Step-by-step explanation:
Alright, lets remember that sin(x) is odd function, which means that
wherever you watch an expression like this: sin(-a), you can use the odd functions property, and turn it like the following
sin(-a)= - sin(a)
Now, other thing to remember:
So, we can obtain any value for sin(x) function starting from the opposite function, cos(x), using the following:
So, if cos(a)= - 8 / 17, using the above equation we obtain the value for sin(a)
Using the odd function property, we get the following result
sin(-a)= - sin(a) = -15/17