Yo, some questions.

As in how do u do these. Thanks.

T5 = 3T2 and S6= 36, find the first three terms.

also

Sn = 5n2(sqaured that is) + 3n - Find the first three terms and thus find a formula for Tn

Sweet as Thanks.

- October 26th 2008, 05:37 AMDevArithmetic Sequences - T5 = 3T2 and S6= 36, find the first three terms.
Yo, some questions.

As in how do u do these. Thanks.

T5 = 3T2 and S6= 36, find the first three terms.

also

Sn = 5n2(sqaured that is) + 3n - Find the first three terms and thus find a formula for Tn

Sweet as Thanks. - October 26th 2008, 06:19 AMjames_bond
and we know that so . And we were also given: . Using this: . So the first three terms: .

For the second problem: . You can see that and therefore and the first three terms: . - October 26th 2008, 06:43 AMSoroban
Hello, Dev!

We are expected to know these formulas:

. .

. .

. . . . where: .

Quote:

Find the first three terms.

5th term: .

.[1]

.[2]

Substitute [1] into [2]: .

Substitute into [1]: .

The first term is 1, the common difference is 2.

Therefore, the first three terms are: .1, 3, 5.

- October 26th 2008, 07:09 AMSoroban
Hello again, Dev!

Quote:

Find the first three terms and thus find a formula for

The sum of the first*one*term is: .

The formula says: .

. . Hence: . .[1]

The sum of the first*two*terms is: .

The formula says: .

. . Hence: . .[2]

Substitute [1] into [2]: .

The first term is: . . . the common difference is: