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प्रश्न
For the AP: –3, –7, –11, ..., can we find directly a30 – a20 without actually finding a30 and a20? Give reasons for your answer.
पर्याय
True
False
उत्तर
This statement is True.
Explanation:
Given
First term, a = – 3
Common difference, d = a2 – a1
= – 7 – (– 3)
= – 4
a30 – a20 = a + 29d – (a + 19d)
= 10d
= – 40
It is so because difference between any two terms of an AP is proportional to common difference of that AP.
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