Use sah coh toa. Sin cos and tan
All three series converge, so the answer is D.
The common ratios for each sequence are (I) -1/9, (II) -1/10, and (III) -1/3.
Consider a geometric sequence with the first term a and common ratio |r| < 1. Then the n-th partial sum (the sum of the first n terms) of the sequence is
Multiply both sides by r :
Subtract the latter sum from the first, which eliminates all but the first and last terms:
Solve for :
Then as gets arbitrarily large, the term will converge to 0, leaving us with
So the given series converge to
(I) -243/(1 + 1/9) = -2187/10
(II) -1.1/(1 + 1/10) = -1
(III) 27/(1 + 1/3) = 18
First, take the written expression apart. Four times a number would be 4n. Then the difference between. That would be a subtract sign. Then finally the seven. The difference between 4n and 7 so:
4n - 7 is your answer.
165 rounded to the nearest front (the hundreds place for all of them in this case) is 200. 123 rounded to the nearest hundred is 100, 376 rounded to the nearest hundred is 400, and 134 rounded to the nearest hundred is 100. Adding 200 + 100 + 400 + 100, we get 800.
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Hope this helps!
60 and 60 are both the same number.
