SPM 2022 Add Maths Paper 1, Question 3Indices, Surds & Logarithms

Solved on video in English and Bahasa Melayu · Form 4, Indices, Surds & Logarithms · 4:19 video

The question

(a)

3 (a) Derive that log_a mn = log_a m + log_a n.

(b)

(b) Hence, find the value of u if log_u(u + 3) + log_u(u − 1) = 2.

Step 1

Let log_a m = x and log_a n = y.

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

Final answer

Derived

Where students lose marks

Watch out: derive it from m = a^x and n = a^y. Using the log law itself is circular and loses marks.

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

Final answer

u = 3/2

Where students lose marks

Watch out: always write the step combining the two logs with the product law. Skipping it loses marks even if u is correct.

Watch every step of this question solved on video (4:19), 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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