11,1,-9,-19,-29 3/30/2014 | Liza from Fountain, CO | 2 Answers | 0 Votes Mark favorite Subscribe Comment
An=a+d(n-1) An=11+(-10)(n-1) An=11-10n+10 An=21-10n check: n=1, An=21-10(1)=21-10=11 n=2, An=21-10(2)=21-20=1 n=3, An=21-10(3)=21-30=-9 n=4, An=21-10(4)=21-40=-19 n=5, An=21-10(5)=21-50=-29 3/30/2014 | Arthur D. Comment
You have to employ the formula Explicit formula is given as a_{n} = a_{1} + (n – 1)d From the given sequence: 11,1,-9,-19,-29 a = 11, d = 10 and n = 5 a_{n} = 11 + (n – 1)10 a_{n} = 11 +10n - 10 a_{n} = 10n - 1 and that is your explicit formula. 3/30/2014 | IBRAHIM A. Comment