the fourth term of an ap is zero then prove that 25th term of an ap is 3 times 11th term
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5
Answer:
Step-by-step explanation:
Given a4 = 0 That is (a + 3d) = 0 ⇒ a = - 3d → (1) nth term of AP is given by an = a + (n – 1)d a11 = a + 10d = – 3d + 10d = 7d [From (1)] a25 = a+ 24d = – 3d + 24d = 21d [From (1)] = 3 x 7d Hence a25 = 3 x a11
Answered by
14
Here is ur answer.........
Let a be the first term and d be the common difference.
Given, a4 = 0
==> a + 3d = 0
==> a = -3d
Now, a25 = a + 24d
==> a25 = 24d - 3d = 21d
and, a11 = a + 10d
==> a11 = 10d - 3d
==> a11 = 7d
But 21d = 3(7d)
==> a25 = 3(a11)
Hope it helps!!
Let a be the first term and d be the common difference.
Given, a4 = 0
==> a + 3d = 0
==> a = -3d
Now, a25 = a + 24d
==> a25 = 24d - 3d = 21d
and, a11 = a + 10d
==> a11 = 10d - 3d
==> a11 = 7d
But 21d = 3(7d)
==> a25 = 3(a11)
Hope it helps!!
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