5^ (2x) - 3*5^x = 18 find using natural logs

Question

Mathematics

Olivia Dawson

24 June, 02:36

5^ (2x) - 3*5^x = 18 find using natural logs

+3

Answers (2)

Know the Answer?

Davis · Answer 1

Step-by-step explanation:

hello:

let : 5^x = t ... t > 0

note : 5^ (2x) = (5^x) ²

you have : t²-3t-18=0

(t-6) (t+3) = 0

t-6=0 or t+3=0

t = 6 or t = - 3 (refused)

but : 5^x = t so : 5^x = 6

using natural logs : log (5^x) = log6

x log5 = log6

x = log6/log5

Elisabeth Andrade · Answer 2

Elisabeth Andrade 24 June, 06:11

0

Yes because 5^ (2x) is 18/34