show that if the first number of an infinite geometric series is 1 and the common ratio is 1/c then the sum is c/c-1

show that if the first number of an infinite geometric series is 1 and

1.	show that if the first number of an infinite geometric series is 1 and the common ratio is 1/c then the sum is c/c-1
Answer» INFINITE sum of G.P is given by 1−ra =4AND second term is given to be 43 hence ar= 43 so let US solve the above TWO equations :a= 4r3 ⇒ 4r(1−R)3 =4⇒16r(1−r)=3⇒16r−16r 2 =3⇒16r 2 −16r+3=0⇒(4r−1)(4r−3)=0⇒r= 41 , 43 and ⇒a= 4r3 =3,1so the ordered pair (a,r)=(3, 41 ),(1, 43 )I hope this will help you