Science talk:Math Exam Resources/Courses/MATH100/December 2012/Question 03 (a)

Hi!

I used a different method to solve this problem and got the same answer. I'll write it out below in case anybody finds it easier :)

We all know the following equation:
(y-y0) = m(x-x0)
where y = f(x), m = f '(x) and x0 and y0 are the coordinates that the tangent line passes through.

In this case we are given two y0s and x0s and x = 1, so we can create the two following equations:

f(1)-3 = f '(1)(1+2)

f(1)-5 = f '(1)(1-0)

Now we have two equations and two variables to solve for. Simple algebra gives us f(1) = 6 and f'(1) = 1. Tada! I hope you found this useful :)

Hello Kristina,

We've added your solution as an extra solution! Thanks for the suggestion!