Find the first, fourth, and tenth terms of the arithmetic sequence described by the given rule. A(n)=-2+(n-1)(-2.2)
To find the terms of an arithmetic sequence, we need to use the formula for the nth term of an arithmetic sequence. The formula is given by:
A(n) = a + (n-1)d
where A(n) represents the nth term, a represents the first term, n represents the position of the term, and d represents the common difference between the terms.
Given the rule A(n) = -2 + (n-1)(-2.2), we can identify that the first term (a) is -2, and the common difference (d) is -2.2.
To find the first term, we substitute n = 1 into the formula:
A(1) = -2 + (1-1)(-2.2)
A(1) = -2 + (0)(-2.2)
A(1) = -2 + 0
A(1) = -2
Therefore, the first term of the arithmetic sequence is -2.
To find the fourth term, we substitute n = 4 into the formula:
A(4) = -2 + (4-1)(-2.2)
A(4) = -2 + (3)(-2.2)
A(4) = -2 + (-6.6)
A(4) = -8.6
Therefore, the fourth term of the arithmetic sequence is -8.6.
To find the tenth term, we substitute n = 10 into the formula:
A(10) = -2 + (10-1)(-2.2)
A(10) = -2 + (9)(-2.2)
A(10) = -2 + (-19.8)
A(10) = -21.8
Therefore, the tenth term of the arithmetic sequence is -21.8.
In summary, the first term is -2, the fourth term is -8.6, and the tenth term is -21.8 in the arithmetic sequence described by the rule A(n) = -2 + (n-1)(-2.2).
A(n)=-2+(n-1)(-2.2)
= -2 - 2.2n + 2.2
= .2 - 2.2n
since term numbers are labeled with whole numbers, n ≥ 1
and the first term is -2
and the common difference is -2.2
the fourth term = a + 3d = -2 + 3(-2.2) = -8.6
then tenth term = .....
what, you can't plug in values?
A(1) = -2+(1-1)(-2.2) = -2
A(2) = -2+(2-1)(-2.2)
and so on
hint. Just keep subtracting 2.2 to get the next term.
3.
Find the first, fourth, and tenth terms of the arithmetic sequence described by the given rule.
A(n) = –3 + (n – 1)(–2.2)
–2.2, –11.8, –19.8
–3, –9.6, –22.8
–3, –11.8, –25
0, –6.6, –19.8
The answer is either letter A, letter B, or letter C