Q. 14.7( 3 Votes )

Write the first three terms of the following sequences whose nth terms are given by

(i) (ii) cn = (–1)n3n+2 (iii)

Answer :

(i) Here, an =


For n = 1, a1 = = =


For n = 2, a2 = = = = 0


For n = 3, a3 = = = = 1


Hence, the first three terms of the sequence are, 0 and 1.


(ii) Here, cn = (-1)n 3n + 2


For n = 1, c1 = (-1)1 31 + 2 = (-1) 33 = (-1) (27) = -27


For n = 2, c2 = (-1)2 32 + 2 = (1) 34 = (1) (81) = 81


For n = 3, c3 = (-1)3 33 + 2 = (-1) 35 = (-1) (243) = -243


Hence, the first three terms of the sequence are -27, 81 and -243.


(iii) Here, zn =


For n = 1, z1 = = =


For n = 2, z2 = = = = 2


For n = 3, z3 = = =


Hence, the first three terms of the sequence are, 2 and.


Rate this question :

How useful is this solution?
We strive to provide quality solutions. Please rate us to serve you better.
Related Videos
Interactive Quiz:Euclid's Division LemmaInteractive Quiz:Euclid's Division LemmaInteractive Quiz:Euclid's Division Lemma44 mins
Fundamental Theorem of Arithmetic-2Fundamental Theorem of Arithmetic-2Fundamental Theorem of Arithmetic-238 mins
Champ Quiz | Fundamental Principle Of ArithmeticChamp Quiz | Fundamental Principle Of ArithmeticChamp Quiz | Fundamental Principle Of Arithmetic41 mins
Fundamental Theorem of Arithmetic- 1Fundamental Theorem of Arithmetic- 1Fundamental Theorem of Arithmetic- 143 mins
Euclids Division LemmaEuclids Division LemmaEuclids Division Lemma49 mins
NCERT | Imp. Qs. on Rational and Irrational NumbersNCERT | Imp. Qs. on Rational and Irrational NumbersNCERT | Imp. Qs. on Rational and Irrational Numbers44 mins
Quiz | Imp Qs on Real NumbersQuiz | Imp Qs on Real NumbersQuiz | Imp Qs on Real Numbers37 mins
Relation Between LCM , HCF and NumbersRelation Between LCM , HCF and NumbersRelation Between LCM , HCF and Numbers46 mins
Application of Euclids Division LemmaApplication of Euclids Division LemmaApplication of Euclids Division Lemma50 mins
Quiz | Fun with Fundamental Theorem of ArithmeticQuiz | Fun with Fundamental Theorem of ArithmeticQuiz | Fun with Fundamental Theorem of Arithmetic51 mins
Try our Mini CourseMaster Important Topics in 7 DaysLearn from IITians, NITians, Doctors & Academic Experts
Dedicated counsellor for each student
24X7 Doubt Resolution
Daily Report Card
Detailed Performance Evaluation
caricature
view all courses