Date | May 2018 | Marks available | 2 | Reference code | 18M.1.SL.TZ2.S_10 |
Level | Standard Level | Paper | Paper 1 | Time zone | Time zone 2 |
Command term | Find | Question number | S_10 | Adapted from | N/A |
Question
Consider a function . The line L1 with equation is a tangent to the graph of when
Let and P be the point on the graph of where .
Write down .
Find .
Show that the graph of g has a gradient of 6 at P.
Let L2 be the tangent to the graph of g at P. L1 intersects L2 at the point Q.
Find the y-coordinate of Q.
Markscheme
recognize that is the gradient of the tangent at (M1)
eg
(accept m = 3) A1 N2
[2 marks]
recognize that (M1)
eg
A1 N2
[2 marks]
recognize that the gradient of the graph of g is (M1)
choosing chain rule to find (M1)
eg
A2
A1
AG N0
[5 marks]
at Q, L1 = L2 (seen anywhere) (M1)
recognize that the gradient of L2 is g'(1) (seen anywhere) (M1)
eg m = 6
finding g (1) (seen anywhere) (A1)
eg
attempt to substitute gradient and/or coordinates into equation of a straight line M1
eg
correct equation for L2
eg A1
correct working to find Q (A1)
eg same y-intercept,
A1 N2
[7 marks]