NCERT Class XI Mathematics - Sequences and Series - Solutions

Question : 37

Total: 106

The 4th term of a G.P. is square of its second term, and the first term is – 3. Determine its 7th term.

Solution:

We have a = – 3, a4 = (a2)2
⇒ ar3 = (ar)2 ⇒ ar3 = a2r2 ⇒ r = a = – 3 (Since a = – 3)
∴ a7 = ar6 = – 3 (–3)6 = –2187

Go to Question:

Prev Question

Next Question