SPM 2018 Add Maths Paper 1, Question 21Quadratic 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 quadratic equation hx² - 3x + k = 0, where h and k are constants, has roots β and 2β. Express h in terms of k.

[3 marks]

Step 1

Compare hx² - 3x + k = 0 with ax² + bx + c = 0 to identify a = h, b = -3, c = k.

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

Final answer

h = 2/k

Where students lose marks

Watch out: sum of roots is −b/a (so +3/h here), product is c/a, and substitute β = 1/h into the product before solving.

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.

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