Question

If r = -\sqrt{2}, and a5 = \sqrt{2}, what is the first term of the sequence?

Answer 1

Answer: C

Step-by-step explanation:

Let x represent the first term (a₁)

a₁ = x

a₂ = x(-√2)  = -x√2

a₃ = -x√2(-√2)  = 2x

a₄ = 2x(-√2)   = -2x√2

a₅ = -2x√2(-√2)   = 4x

Since it is given the a₅ = √2, then we  can solve: 4x =√2

Divide both sides by 4 to get: x = $\frac{\sqrt{2}}{4}$

this can also be written as: $\frac{1}{4}\sqrt{2}$