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Date:
Day 1
4. F-IF.1.3
Find the first five terms of the recursive sequence defined by the function below. 
f(n)=2f(n-1)+3n, where 
f(1)=-2
5. F-LE.1.2
The third term in an arithmetic sequence is 10 and the fifth term is 26 . If the first term is 
a_(1), which is an equation for the 
nth term of this sequence?

Date:\newlineDay 11\newline44. F-IF.11.33\newlineFind the first five terms of the recursive sequence defined by the function below. f(n)=2f(n1)+3n f(n)=2 f(n-1)+3 n , where f(1)=2 f(1)=-2 \newline55. F-LE.11.22\newlineThe third term in an arithmetic sequence is 1010 and the fifth term is 2626 . If the first term is a1 a_{1} , which is an equation for the n n th term of this sequence?

Full solution

Q. Date:\newlineDay 11\newline44. F-IF.11.33\newlineFind the first five terms of the recursive sequence defined by the function below. f(n)=2f(n1)+3n f(n)=2 f(n-1)+3 n , where f(1)=2 f(1)=-2 \newline55. F-LE.11.22\newlineThe third term in an arithmetic sequence is 1010 and the fifth term is 2626 . If the first term is a1 a_{1} , which is an equation for the n n th term of this sequence?
  1. Calculate f(3)f(3): Now, let's find f(3)f(3).
    f(3)=2f(31)+3×3f(3) = 2f(3-1) + 3\times3
    f(3)=2f(2)+9f(3) = 2f(2) + 9
    f(3)=2×2+9f(3) = 2\times2 + 9
    f(3)=4+9f(3) = 4 + 9
    f(3)=13f(3) = 13
  2. Calculate f(4)f(4): Next, we calculate f(4)f(4).
    f(4)=2f(41)+3×4f(4) = 2f(4-1) + 3\times4
    f(4)=2f(3)+12f(4) = 2f(3) + 12
    f(4)=2×13+12f(4) = 2\times13 + 12
    f(4)=26+12f(4) = 26 + 12
    f(4)=38f(4) = 38
  3. Calculate f(5)f(5): Finally, we find f(5)f(5).\newlinef(5)=2f(51)+3×5f(5) = 2f(5-1) + 3 \times 5\newlinef(5)=2f(4)+15f(5) = 2f(4) + 15\newlinef(5)=2×38+15f(5) = 2 \times 38 + 15\newlinef(5)=76+15f(5) = 76 + 15\newlinef(5)=91f(5) = 91
  4. Write nth term: Now we can write the nth term of the arithmetic sequence.\newlineThe nth term an=a1+(n1)da_n = a_1 + (n - 1)d\newlineSince we know d=8d = 8, we substitute it into the equation.\newlinean=a1+(n1)×8a_n = a_1 + (n - 1)\times 8
  5. Find a1a_{1}: To find a1a_{1}, we use the third term which is 1010.\newline10=a1+(31)810 = a_{1} + (3 - 1)\cdot8\newline10=a1+2810 = a_{1} + 2\cdot8\newline10=a1+1610 = a_{1} + 16\newlinea1=1016a_{1} = 10 - 16\newlinea1=6a_{1} = -6

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