SOLUTION: Determine the x value on this sequence (16,35,x,91) and T1,T5and T2 are not given

Algebra.Com
Question 947874: Determine the x value on this sequence (16,35,x,91) and T1,T5and
T2 are not given

Answer by Edwin McCravy(20056)   (Show Source): You can put this solution on YOUR website!
y,z,16,35,x,91

Assume the general term is quadratic: 

 <--general term

Substituting n=3, T3=16





Substituting n=4, T2=35





Substituting n=6, T6=91





We have the system of equations:



Solve that system of equation and get

A=3, B=-2, C=-5

Substitute into our assumed general term:




. Substituting n=5






. Substituting n=1






. Substituting n=1







The sequence is -4,3,16,35,60,91,128,171,220,275,336,403,...

Edwin

RELATED QUESTIONS

the first three terms of a geometric sequence are: T1:T2:T3. if T2=T1+4 and T3=T2+9,... (answered by fractalier)
The first three terms of a geometric sequence are: T1 ; T2 ; and T3. If T2 = T1 + 4 and... (answered by Theo)
Chains support a​ crate, as shown on the right. The equations relating tensions... (answered by Fombitz)
Chains support a​ crate, as shown on the right. The equations relating tensions... (answered by Alan3354)
Chains support a​ crate, as shown on the right. The equations relating tensions... (answered by richwmiller)
The first three terms of a geometric sequence are t1 = 32, t2 = -16, t3 = 8. Find the... (answered by ikleyn)
Given the figure with L1 // L2 and T1 // T2 Prove that ∠x ≅ ∠y figure:... (answered by mananth)
Help would be much appreciated with the following question. The standard equation of a (answered by )
Help would be much appreciated with the following question. The standard equation of a (answered by longjonsilver)