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# Even moar trig watch

1. Same interval for x as last time
0°≤x≤360°

4cosx(cosx-1)=-5cosx

i did
4cos²x-4cosx=-5cosx
4cos²x+cosx=0
cosx(4cosx+1)=0

but there's no answer in the back of the book which says that 0°,180°or 360° are answers
2. (Original post by thefatone)
Same interval for x as last time
0°≤x≤360°

4cosx(cosx-1)=-5cosx

i did
4cos²x-4cosx=-5cosx
4cos²x+cosx=0
cosx(4cosx+1)=0

but there's no answer in the back of the book which says that 0°,180°or 360° are answers
That would be because does not yield or as solution, that would be . when and I'll let you find the other solution.
3. (Original post by thefatone)
Same interval for x as last time
0°≤x≤360°

4cosx(cosx-1)=-5cosx

i did
4cos²x-4cosx=-5cosx
4cos²x+cosx=0
cosx(4cosx+1)=0

but there's no answer in the back of the book which says that 0°,180°or 360° are answers
You have done it correctly but cosx is not 0 when x=0,180 or 360
4. Thanks a bunch all i'll probably be posting loads more threads since i'll probably need more help on these xD
5. (Original post by thefatone)
Thanks a bunch all i'll probably be posting loads more threads since i'll probably need more help on these xD
I am too late to help?
6. (Original post by thefatone)
Thanks a bunch all i'll probably be posting loads more threads since i'll probably need more help on these xD

(Original post by TeeEm)
I am too late to help?
You snooze you lose
7. (Original post by Zacken)

You snooze you lose
I am glad you are doing more than your fair bit as I feel very "cannot be bothered" recently
8. My girl bled a bit. She had the best time tho in missionary, doggy style was orite too
9. (Original post by TeeEm)
I am glad you are doing more than your fair bit as I feel very "cannot be bothered" recently
No problemo! You deserve a break.

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