SPM 2019 Add Maths Paper 1, Question 10Indices, Surds & Logarithms

Solved on video in English and Bahasa Melayu · 4 marks · Form 4, Indices, Surds & Logarithms · 4:59 video

The question

Given log_m C = x, express in terms of x: (a) log_m(1/C), (b) log_{sqrt(m)}(C m³.

[4 marks]

Step 1

log_m(1/C) = log_m(C⁻¹ = -log_m C = -x.

Why this step

1/C is the same as C⁻¹. Once it's a power, the power law lets us pull the −1 out front and use log_m C = x.

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

Final answer

(a) −x (b) 2(x+3) = 2x + 6

Where students lose marks

Watch out: in change of base, put log_m(Cm³) on top and log_m(√m) below, and remember log_m(m¹/2)) = 1/2, not 2.

Watch every step of this question solved on video (4:59), 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.

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