Ch 11.1-11.3 Explicit Sequence

Write the explicit equation for the nth term of the arithmetic sequence

-8, -5.5, -3, ...

a_n = ___________________

Simplify the expression.

• 2.5n - 10.5

• -8 - 2.5n

• -3 - 2.5n

• -8 -3n

Write the explicit equation for the nth term of the geometric sequence 45, 90, 180, 360,...

a_n= ____________

Simplify the expression.

• a_n = 2(45)ⁿ

• a_n = 2(45)^n-1

• a_n = 45(2)ⁿ

• a_n = 45(2)^n-1

Find a₇₅ in the sequence -8, -5.5, -3, ...

Find a₁₂ in the sequence 3, 12, 48, 192, ...

Find the three arithmetic means between -21, ____, _____, _____, -5.

Use commas to separate but do NOT use spaces.

Find the three geometric means between

-9, ____, ____, ____, -1/9

Use commas to separate but do NOT use spaces.

Find the 21st term of the sequence for which

a₁= 5 and d = 2

Find the 21st term of the sequence for which

a₁= 5 and r = 2

Given two terms of each arithmetic sequence, find a₁ and d.

a₄=-34.5 and a₈=53.5

a₁ = _____ , d = ______

Given two terms of the geometric sequence, find a₁and r.

a₅= 768 and a₁₀=786,432

a₁= _____ , r = _____