Question

tn=5^10, a=5,r=5 find n​

Answer 1

Answer:

tn=ar^n-1

5^10/5=5^n-1

5^9=5^n-1

bases are equal so powers are also equal

n-1=9

n=1+9=10

Answer 2

Answer:

Tn : 50

a: 5

r or l : 5

sum of nth terms : Sn = a/2× (n +l )

50 =5/2 ×(n+5)

50×2 =5× (n+5)

100= 5n + 5

5-100=5n

-95 =5n

*n=-19*