Solve the equation: 5^(2x+1) = 7, giving your answer correct to four decimal places.

First, we take logs of both sides: log(5^(2x+1))=log(7) Now, using the 3rd law of logs (index rule; using the power as the coefficient), we get: (2x+1)log(5)=log(7) i.e. 2x+1 = (log(7))/(log(5)) = 1.20906... Therefore, 2x=1.209...- 1 = 0.20906... i.e. x = 0.209.../2 = 0.10453... x = 0.1045 (c.t. 4d.p.)

Answered by Mohamad S. Maths tutor

8609 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

Find the exact solution of the following equation: e^(4x-3) = 11


I'm confused about differentiation and integration, could you explain these to me?


How do I find the inverse of a function?


What is the integral of (6x^2 + 2/x^2 + 5) with respect to x?


We're here to help

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