An Yi's answer to Hello's Secondary 4 A Maths Singapore question.

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An Yi
An Yi's answer
76 answers (Tutor Details)
Hello, this is how I did it. Since both sides of the equation has “2x”, you can sub 2x = y, and no need to use the cos2x or sin2x formulas. Hope this helps!
Eric Nicholas K
Eric Nicholas K
2 years ago
Actually, secant is 1 divided by cosine…