`a_n = (-1)^(n+1)(2/n)` Write the first five terms of the sequence.

`a_n=(-1)^(n+1)(2/n)`

The subscript n represents the term number. It usually starts with n=1 which tells that a1 is the first term.

So to determine the first five terms, plug-in n={1,2,3,4,5}.

When n=1, the first term is:

`a_1=(-1)^(1+1)(2/1)`

`a_1=2`

When n=2, the second term is:

`a_2=(-1)^(2+1)(2/2)`

`a_2=-1`

When n=3, the third term is:

`a_3=(-1)^(3+1)(2/3)`

`a_3=2/3`

When n=4, the fourth term is:

`a_4=(-1)^(4+1)(2/4)`

`a_4=-1/2`

And when n=5, the fifth term is:

`a_5=(-1)^(5+1)(2/5)`

`a_5=2/5`

Therefore, the first five terms of the sequence are `{2,-1,2/3,-1/2,2/5}` .

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