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secondary 3 | A Maths
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Date Posted: 3 years ago
Views: 217
(1 + cosx + cos 2x) / (sinx + sin2x)
= (cos²x + sin²x + cosx + cos²x - sin²x) / ( sinx + 2sinxcosx)
= (2cos²x + cosx) / (sinx + 2sinxcosx)
= (2cosx + 1)(cosx) / [(2cosx + 1)(sinx)]
= cosx / sinx
= cotx
= (cos²x + sin²x + cosx + cos²x - sin²x) / ( sinx + 2sinxcosx)
= (2cos²x + cosx) / (sinx + 2sinxcosx)
= (2cosx + 1)(cosx) / [(2cosx + 1)(sinx)]
= cosx / sinx
= cotx
See 1 Answer
done
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clear
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The first thing we start off with is the conversion from 2x to x, since you would probably have noticed the differences between the angles.
We have to choose a good form of cos 2x to use so that we can simplify the expression.
We have to choose a good form of cos 2x to use so that we can simplify the expression.
Date Posted:
3 years ago
It depends on which you choose. The 1 could be converted as well
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