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Find the coordinates of the point on the curve y= 2x(squared) - 7x +10

where the tangent of the curve makes an angle of 45' wuth the positive direction of the x-axis.

help!

em...

you would use that formula maybe

b(squared)- (sqrt 4*a*c)/2a

where a=2, b=-7, c=10

actually that's probably wrong, looks good tho eh?

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Guest Zeenat Aman
I dunno' date=' but you spelt both "Asian" and "Morissette" wrong in your profile...

Sorry.[/quote']

I wondered when you were going to edit that.

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this is what i got:

gradient of tangent: tan45= 1

so equation is y=x+c

set x(squared) -7x +10 = to x+c to give you

2xsquared - 8x +10 -c=0

then using discrimiannt bsquared - 4ac, you get c to equal -3

so the equation of the tangent is y=x-3

please tell me that's right! higher maths tomorrow!

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Not ignorant at all because he is correct. Let this be a lesson to you; Mathematics erodes your soul.

hes not correct, because he implied that im 100% british trying to be a yank.

but i learned to speak in hong kong in an international school, so im naturally im going to speak/type how i was taught.

so stop being so fucking ignorant

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I think he was simply saying that when in Rome, do as the Romans do so to speak. If you have been taught using American English then fair enough, but at least make an effort to use what standard English is in this country. You obviously didn't learn what ignorant means in Hong Kong either.

But this is a pointless clash. Back to your revision - all I can say is good luck - at least I had the sense to quit this horrible subject when the chance arose...

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y= 2x(squared) - 7x +10

dy/dx = 4x - 7

gradient = tan 45' = 1 = dy/dx

4x - 7 = 1

4x = 8

x = 2

x = 2: y = 2(4) - 7(2) + 10 = 4

Ans: (2,4)

..i think. I do maths at uni but I'm spectacularly bad at it... 'pologies if youve already had your exam or whatever.

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this is what i got:

gradient of tangent: tan45= 1

so equation is y=x+c

set x(squared) -7x +10 = to x+c to give you

2xsquared - 8x +10 -c=0

then using discrimiannt bsquared - 4ac' date=' you get c to equal -3

so the equation of the tangent is y=x-3

please tell me that's right! higher maths tomorrow![/quote']

clever. i was really shit at maths. 2 slices of bread + 2 slices of cheese = cheese sandwich.that is as far as my brain can take me im afraid.....

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