Wong Wei Jie's answer to mouse's Secondary 3 A Maths Singapore question.

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Wong Wei Jie
Wong Wei Jie's answer
24 answers (Tutor Details)
1st
For step 1, to do trial & error for factors of f(x), use factors of the constant if possible (6 in this case, so possible factors for trying are 2, -2, 3 and -3) to reduce your time used for trial & error. Hope you understand