Science:Math Exam Resources/Courses/MATH104/December 2010/Question 01 (n)/Solution 1

From UBC Wiki

We use the linear approximation of at to estimate . (Approximating at x = 1 is a logical choice, as 1 is close to 0.8, and we know that .)

We know , which is equal to 1 when . Substituting this into the linear approximation formula, we get,