SPM 2020 Add Maths Paper 1, Question 15Differentiation

Solved on video in English and Bahasa Melayu · 4 marks · Form 5, Differentiation · 3:53 video

The question

The normal to the curve y = x² - 5x at point P is parallel to the straight line y = -(1/3)x + 12. Find the coordinates of P.

[4 marks]

Step 1

The line y = -(1/3)x + 12 has gradient -1/3; the normal at P is parallel to it, so the normal's gradient is -1/3.

5 more steps, each with the reason for it, in the full solution

Final answer

P = (4, −4)

Where students lose marks

Watch out: get y from the curve y = x² − 5x, not from dy/dx, or you will wrongly get (4, 3).

Watch every step of this question solved on video (3:53), with the reason behind each step and a box that checks your own answer.

No card. Every past-year question on video, in English and BM.