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Trig identities question (maths)

Please help me with this question:

Show that 2cos^2x + 3sinx=3 may be written as 2sin^2x - 3sinx+1=0.

---Moved to Maths---
(edited 7 years ago)
Try replacing cos2x cos^{2}x by making it the subject of the identity

cos2x+sin2x=1cos^{2}x + sin^{2}x = 1
Reply 2
Original post by tajtsracc
Since there's isn't any cos in the second equation, you should probably substitute cos2x in the first equation with an identity to get rid of it.


Oh i think I understand now thank you
Reply 3
Original post by Astro_Joe
Try replacing cos2x cos^{2}x by making it the subject of the identity

cos2x+sin2x=1cos^{2}x + sin^{2}x = 1


Thanks

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