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A mathematician has devised a formula that produces a serie
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05 Jun 2017, 02:22
05 Jun 2017, 02:22
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Question Stats:
81% (01:35) correct
18% (01:48) wrong based on 127 sessions
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A mathematician has devised a formula that produces a series of numbers \(s_1 , s_2, \dots, s_x\) according to the principles \(s_1 = 2, s_2 = 2, s_3 = 2\), and for \(x \geq 4\), \(s_X = 2*s_{X-1} + s_{X-2}\) . Which of the following equals \(s_6=\) ?
A) 30
B) 34
C) 37
D) 38
E) 40
Re: A mathematician has devised a formula that produces a serie
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30 Mar 2019, 03:33
30 Mar 2019, 03:33
anyone please solve this problem
Re: A mathematician has devised a formula that produces a serie
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30 Mar 2019, 05:09
30 Mar 2019, 05:09
Expert Reply
Sure. We are here to help the students.
Now, the problem looks difficult but indeed it is can be solved just using substitution and follow the guidelines.
\(S_4 = 2 * S_3 + S_2\) According with the stem \(S_3=2\) and \(S_2=2\)
Substitute
\(S_4 = 2 * 2 + 2 = 6\)
\(S_5 = 2 * S_4 + S_3 = 2 * 6 + 2 = 14\)
\(S_6 = 2* S_5 + S_4 = 2 * 14 + 6 = 34\)
B is the answer.
Hope this helps
Regards
Now, the problem looks difficult but indeed it is can be solved just using substitution and follow the guidelines.
\(S_4 = 2 * S_3 + S_2\) According with the stem \(S_3=2\) and \(S_2=2\)
Substitute
\(S_4 = 2 * 2 + 2 = 6\)
\(S_5 = 2 * S_4 + S_3 = 2 * 6 + 2 = 14\)
\(S_6 = 2* S_5 + S_4 = 2 * 14 + 6 = 34\)
B is the answer.
Hope this helps
Regards
