Answer:
B
Step-by-step explanation:
A geometric series will only converge if the common ratio r meets the requirement
- 1 < r < 1
The n th term of a geometric sequence is
= a
where a is the first term and r the common ratio
All terms inside the summation are of this form
The only one with - 1 < r < 1 is B where r =
= 0.75
Use cosine law to solve the problem. See image attached.
What we're looking for is the length of side A (a side which is opposite with angle A).
This is the formula of cosine law
A² = B² + C² - 2BC cos A
Input the numbers
A² = 75² + 90² - 2(75)(90) cos 85°
A =

A =
Question 1: 6 3/4 so option b
3x3x3x3 = 81
x.x.x.x = x^4
2x2x2x2 = 16
B. 81x^4/16
Answer:
15
Step-by-step explanation:
following PEMDAS, we don't have () so we move on to exponents
5^2 is equal to 5 x 5 which is 25
40-25=15