The second and fifth terms of a geometric series are 750 and -6 respectively. Find: (1) the common ratio; (2) the first term of the series; (3) the sum to infinity of the series

xn = ar(n-1)(1) x2 = 750 = ar1(2) x5 = -6 = ar4divide second equation by first-6/750 = r3r3 = -0.008r= -0.2Insert into first equation.750 = a * -0.2a = -3750Sum to infinite series = a(1/(1-r))(insert known variables)Sum to infinite series = -3750 * 1/1.2= -3125

Answered by Henry P. Maths tutor

5018 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

Sketch the graph y = 2sin(4x)


The weight in grams, of beans in a tin is normally distributed with mean U and S.D. 7.8, given that 10% conntain more than 225g a) Find U b) % of tins that contain more than 225 grams(A2 stats)


Find the integral of ln(x)


Explain briefly the Normal Distribution


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2024

Terms & Conditions|Privacy Policy
Cookie Preferences