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secondary 3 | A Maths
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Hi, pls kindly advise me the working solution for this question please. Thanks a lot !!!
Date Posted: 3 years ago
Views: 275
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Good evening Candice! We use the double angle formula involving angles A and A/2.
Date Posted:
3 years ago
Candice, double angle formulae work for any pairs of angles where one angle is twice the other. The most common one, involving 2A and A, goes like
sin 2A = 2 sin A cos A.
However, it can also work for pairs like 4A and 2A to get
sin 4A = 2 sin 2A cos 2A.
Or even
sin 10A = 2 sin 5A cos 5A.
It also works for smaller angles like
sin A = 2 sin A/2 cos A/2.
sin 2A = 2 sin A cos A.
However, it can also work for pairs like 4A and 2A to get
sin 4A = 2 sin 2A cos 2A.
Or even
sin 10A = 2 sin 5A cos 5A.
It also works for smaller angles like
sin A = 2 sin A/2 cos A/2.
Wow...I learnt something again! Thank you so much, Mr Eric :D
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