Where do start with this im having trouble in trig this year f(n)=f(n-1)+5 and f(1)=-2 then f(20)=?

Question

I need help with figuring out how to answer these questions the choices for answers are

1. 93

2. 98

3. 102

4. 115

 

Answer 1

a_n = a_n-1 + 5, Arithmetic sequence with common difference of 5

a₂₀ = -2 + (19)(5)

 

Can you solve and answer?

Answer 2

This is an example of a recursive definition of a function whose argument is an integer.

(The argument is equivalent to a subscript.)

The definition tells you that each term of the sequence is five more than its immediate predecessor.

This is a topic not in Trigonometry, but Algebra II.