prove that sum of the first 5 consecutive of an arithematic sequences is 5 times its middle term
Answers
Answered by
0
Answer:
Let the terms of AP be
A−2d,a−d,a,a+d,a+2d
A/Q
(a−2d)+(a−d)+a+a(a+d)+(a+2d)=60
5a=60⇒a=12
and a×(a+d)=172+a+2d
⇒a
2
+ad=172+a+2d
⇒144+12d=172+12+2d
⇒12d−2d=184−144=40
⇒10d=40⇒d=4
∴a=12,d=4
and the terms are
12−4×2,12−4,12,12+4,12+2×4
=4,8,12,16,20
Similar questions