Question
Question: Let a<sub>n</sub> be the n<sup>th</sup> term of an A.P. If \(\sum_{r = 1}^{100}a_{2r}\)= a&\(\sum_{r...
Let an be the nth term of an A.P. If ∑r=1100a2r= a&∑r=1100a2r−1= b, then the common difference of the A.P. is
A
a – b
B
b – a
C
2α−β
D
None of these
Answer
None of these
Explanation
Solution
a1 + a3 + a5 +……+ a199 = b
a2 + a4 + a6 +……. + a200 = a
a2 –a1 + a4 – a3 + a6 – a5, ……..+ a200 – a199 = a – b
d + d + d +……+ d = a – b
d = 100α−β