TRIG IDENTITY! math help please!?
[cos4x•tan2x - sin4x] / [cos4x•cot2x + sin4x] = -tan^2(2x)
please show as much work as possible :P thanks so much for your time! I'll select as best answer as soon as yahoo allows me!
hi Josh, I have reported you. Please don't be rude to others. I've seen your other answers and they are very hurtful. If people are asking for advice, do not hurt them and make their situations worse. Please respect the answers community.
- 7 years agoFavorite Answer
hey that was easy than i thought
i thought it will be difficult :)
but it's not :)
finally i did it XD
let do it part by part :)
[cos4x•tan2x - sin4x]
(cos4x * sin2x/cos2x - sin4x)
(cos4x * sin2x - sin4x * cos2x)/cos2x
sin(α – β) = sin(α)cos(β) – cos(α)sin(β)
-sin 2x / cos 2x
[cos4x•cot2x + sin4x]
cos4x * cos 2x/sin2x + sin4x
cos(α – β) = cos(α)cos(β) + sin(α)sin(β)
(cos 4x * cos2x + sin 4x * sin 2x)/sin 2x
-tan^2x <=== answer :)Source(s): grade 12 now :)