What is the 7th term of the geometric sequence where a1 = 4096 and a4 = 64?

To find the 7th term of the geometric sequence, we first need to determine the common ratio of the sequence. In a geometric sequence, each term is obtained by multiplying the previous term by a constant ratio, which we’ll denote as r.

We start with the information given:

  • First term, a1 = 4096
  • Fourth term, a4 = 64

The formula for the nth term of a geometric sequence is:

an = a1 imes rn-1

Using this formula for the fourth term:

a4 = a1 imes r4-1 = a1 imes r3

Substituting the values we know:

64 = 4096 imes r3

To isolate r3, we divide both sides by 4096:

r3 = 64 / 4096

r3 = 1 / 64

Now, to solve for r, we take the cube root of both sides:

r = (1 / 64)1/3

r = 1 / 4

Now that we have the common ratio, we can find the 7th term:

a7 = a1 imes r7-1 = 4096 imes r6

Calculating r6:

r6 = (1 / 4)6 = 1 / 4096

Now we can substitute this back into our equation for a7:

a7 = 4096 imes (1 / 4096) = 1

Thus, the 7th term of the geometric sequence is 1.

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