SPM 2018 Add Maths Paper 1, Question 20Quadratic Functions

Solved on video in English and Bahasa Melayu · 3 marks · Form 4, Quadratic Functions · 4:46 video

The question

It is given that the curve y = (p - 2)x² - x + 7, where p is a constant, intersects with the straight line y = 3x + 5 at two points. Find the range of values of p.

[3 marks]

SPM 2018 Add Maths Paper 1, Question 20: the question as drawn in Eduly's video4:46

Step 1

To find where the curve meets the line, set their y-values equal: (p - 2)x² - x + 7 = 3x + 5.

Why this step

Where the graphs cross they share the same point, so their y-values are equal. Setting them equal gives an equation whose solutions are the crossing x-values.

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

Final answer

p < 4

Where students lose marks

Watch out: move 3x + 5 carefully (−x − 3x = −4x), and use a strict > for two distinct points, not ≥.

Watch every step of this question solved on video (4:46), with the reason behind each step and a box that checks your own answer.

Start 7 days freeAlready a member? Watch it now

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

All questions in SPM 2018 Paper 1

Quadratic Functions: lessons and every past-year question

Baca dalam Bahasa Melayu

More Quadratic Functions questions

Questions are re-typeset by Eduly for study and commentary. Eduly is not affiliated with Lembaga Peperiksaan Malaysia or the Ministry of Education.