Eric Nicholas K's answer to Kathy's Secondary 4 A Maths Singapore question.

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Eric Nicholas K
Eric Nicholas K's answer
5997 answers (Tutor Details)
Q1, Q2, Q3
Eric Nicholas K
Eric Nicholas K
5 years ago
Sorry Kathy, for Q2, angle 2A is obviously in the first quadrant (ie acute) since cos 2A = 119/169 is a positive number.