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Trig q (1 Viewer)
- Thread starter xibu34
- Start date
Deem_Skills
Member
- Joined
- Jul 13, 2022
- Messages
- 71
- Gender
- Male
- HSC
- 2024
do u know your double angle formulae?
sin2x = 2sinxcosx = 2cosxsinx
in this case, x = 3x
so 2cos3xsin3x = sin2(3x) = sin6x
If say the sin3x was replaced with sin3y, you'd have to use your products to sums so its sometimes a bit confusing but if the variables are the same, its double angle and if they're different, it's products to sums
sin2x = 2sinxcosx = 2cosxsinx
in this case, x = 3x
so 2cos3xsin3x = sin2(3x) = sin6x
If say the sin3x was replaced with sin3y, you'd have to use your products to sums so its sometimes a bit confusing but if the variables are the same, its double angle and if they're different, it's products to sums