solving trignometric equations help

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nusrxxt
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can someone please help me with this question
i started with taking sin to the other side to get Pi6
and then solved like usual but my answers were either outside range or doesnt match with the answers
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Last edited by nusrxxt; 1 month ago
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username5737602
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Let x=theta. Since 0<x<pi, 0<2x<2pi and therefore 3/8pi< 2x+3/8pi < 19/8pi. Then just use sin =sin(pi-x) =sin(x+2pi) and you should be good
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sararah04
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--> Make new theta
--> Find all solutions within the new range (using the cast diagram, or other graphs)
--> Rearrange get theta only
--> Check if the final solution is within the original range

Hope this helps!
Last edited by sararah04; 1 month ago
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davros
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(Original post by sararah04)
Hope this helps!
Please edit or delete your post - it is against forum rules to post full solutions!

Thanks
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nusrxxt
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(Original post by sararah04)
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Hope this helps!
Thankyou so much !
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nusrxxt
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(Original post by tej3141)
Let x=theta. Since 0<x<pi, 0<2x<2pi and therefore 3/8pi< 2x+3/8pi < 19/8pi. Then just use sin =sin(pi-x) =sin(x+2pi) and you should be good
thankyouu
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sararah04
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(Original post by davros)
Please edit or delete your post - it is against forum rules to post full solutions!

Thanks
Oh I didn't know it. I'm so sorry about this.
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