In mathematics, the irrational numbers are all the real numbers which are not rational numbers, the latter being the numbers constructed from ratios of integers.
Hj and jk are the same length line segments ( because the midpoint divides a line into two equal parts)
So hj = jk.
hk is the line segment which has the mid point j. It is the double of hj or jk. It can be the sum of hj and jk.
hj + jk = hk
or
2 * hj = hk
or
2 * jk = hk
The sum of the first five terms is 11/2
<h3>How to determine the sum?</h3>
The series is given as:
1/2, -1,2,-4…
Calculate the common ratio of the series using
r = -4/2
Evaluate
r = -2
The sum is then calculated as:

This gives

Evaluate

Evaluate

Hence, the sum of the first five terms is 11/2
Read more about series at:
brainly.com/question/11346378
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