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# 4 cos (2x - (pi /4) ) watch

1. Hi guys, umm...could some1 please give me a hand on this question-i just dont know where to start o

Q) If y = x^2 - x show that the derivative= 1 + ( 2y/x)

Thanx!!
2. dy/dx = 2x-1

1+(2y/x) = 1 + 2(x^2 - x)/x = 1 + (2x^2 - 2x)/x = 1 + 2x - 2 = 2x-1

So we've shown dy/dx = 1 + (2y/x)

..I don't get the thread title btw.
3. y = x^2 - x
dy/dx = 2x - 1

but as y=x^2 - x = x(x-1)
y/x = x-1
2y/x = 2x - 2

so you can write 2x - 1 as 2y/x + 1

so dy/dx = 2y/x + 1
4. thanks! lol, i understand it now. =)

Umm, the thread title...lets not go there lmao-i put it in there by accident, almost posted in the wrong qs & forgot 2 change the title anna. soz, lol
5. hey-i thought i changed ma name o.0 2 rammstein666, grrrrrr
6. Wtf is going on? Who's rammstein666?? And who are you??!
7. Soz i dun know what happened there-i changed ma user name from Chrissi131 to Rammstein666. Bk 2 normal anywho
8. But..but..if you changed your username, then all your posts (past and present) should be under the same name (so those chrissi ones should change too).

Or do you have 2 accounts? (and logging into each back and forth)
9. Sue her!
10. na, i jus got a new user account instead coz i have another e-mail address in use now
11. Umm,...soz i upset u guys, but i didn't mean any harm by it.
12. Oh right. Cool.

(no one's upset tho, just confused)
13. Hey, how could i change my 1st account name?? tried the 'request new username', but i dun know if anything happened.

Soz 4 the confusion =)

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