Answer:
Step-by-step explanation:
You don't need the Law of Cosines, the Law of sines if what you need. You can't use the Law of Cosines because in order to find side a, you would need the length of side c and you don't have it. Using the Law of Sines is appropriate, knowing that angle B = 55:
and solving for a:
so
a = 143.0
Answer:
Option D. is the correct option.
Step-by-step explanation:
In this question expression that represents the kth term of a certain sequence is not written properly.
The expression is .
We have to find the sum of first 10 terms of the infinite sequence represented by the expression given as .
where k is from 1 to 10.
By the given expression sequence will be
In this sequence first term "a" =
and common ratio in each successive term to the previous term is 'r' =
r =
Since the sequence is infinite and the formula to calculate the sum is represented by
[Here r is less than 1]
S =
Now we are sure that the sum of infinite terms is .
Therefore, sum of 10 terms will not exceed
Now sum of first two terms =
Now we are sure that sum of first 10 terms lie between and
Since
Therefore, Sum of first 10 terms will lie between and
.
Option D will be the answer.