Arts (English Medium) कक्षा ११ - CBSE Question Bank Solutions

The n^th term of a sequence is given by a_n = 2n² + n + 1. Show that it is not an A.P.

Find:

 10th term of the A.P. 1, 4, 7, 10, ...

Find: 

18th term of the A.P.

\[\sqrt{2}, 3\sqrt{2}, 5\sqrt{2},\]

Find:

nth term of the A.P. 13, 8, 3, −2, ...

If the sequence < a_n > is an A.P., show that a_m +n +a_m − n = 2a_m.

Which term of the A.P. 3, 8, 13, ... is 248?

Which term of the A.P. 84, 80, 76, ... is 0?

Which term of the A.P. 4, 9, 14, ... is 254?

Is 68 a term of the A.P. 7, 10, 13, ...?

Is 302 a term of the A.P. 3, 8, 13, ...?

Which term of the sequence 24, \[23\frac{1}{4,} 22\frac{1}{2,} 21\frac{3}{4}\]....... is the first negative term?

Which term of the sequence 12 + 8i, 11 + 6i, 10 + 4i, ... is purely real ?

Which term of the sequence 12 + 8i, 11 + 6i, 10 + 4i, ... is purely imaginary?

How many terms are there in the A.P. 7, 10, 13, ... 43 ?

How many terms are there in the A.P.\[- 1, - \frac{5}{6}, -\frac{2}{3}, - \frac{1}{2}, . . . , \frac{10}{3}?\] 

The first term of an A.P. is 5, the common difference is 3 and the last term is 80; find the number of terms.

The 6th and 17th terms of an A.P. are 19 and 41 respectively, find the 40th term.

If 10 times the 10th term of an A.P. is equal to 15 times the 15th term, show that 25th term of the A.P. is zero.